Few things are as endearing to a reader as their favorite character’s blind spots. Especially with such a seemingly omniscient character as Poirot, he is brought down to earth by these simple foibles. From both the books and the TV series (mostly both), here are some of Poirot’s most “humanizing” aspects and traits.
1. His wardrobe. Especially those patent leather shoes; highly impractical, perpetually a cause of pain. But dang it, he wants to look smart. Instead, he ends up covered with sand and dust in “The Adventure of the Egyptian Tomb,” and immerses (and ruins) a pair of suede shoes while helping Arlena Marshall to launch her float in Evil Under the Sun. He knows, on some level, that his get-ups cause consternation to his British acquaintances:
Rowley Cloade was eyeing Poirot rather doubtfully. The flamboyant moustaches, the sartorial elegance, the white spats and the pointed-patent leather shoes all filled this insular young man with distinct misgivings.
Poirot realized this perfectly well, and was somewhat amused. (Taken at the Flood)
But in other stories– perhaps earlier ones– he seems blissfully unaware of his own incongruity to the surrounding landscape.
‘Dear me,’ I complained. ‘There is something about this place that makes me feel extremely conspicuous. As for you, Poirot, you look positively exotic.’
‘You think it is noticed that I am a foreigner—yes?’
‘The fact cries aloud to heaven,” I assured him.
‘And yet my clothes are made by an English tailor,’ mused Poirot. (Dumb Witness)
2. The English language. It seems a bit rich to call Poirot’s slips in English a “blind spot,” considering that he speaks (as per Christie) at least four languages himself– English, French, German, and Italian. He has solved various crimes and decoded clues specifically because of his linguistic skills (including clues in English), sometimes highlighting the Englishman’s lack of a grasp of foreign languages (see: “The Stymphalean Birds,” “The Adventure of the Lost Ball”). But let’s face it– when he does get bewildered over various turns of phrase in English, it’s hilarious.
Miss Lemon replied sadly that servants did not seem to know what elbow grease was nowadays. Poirot looked a little puzzled, but decided not to inquire into the inward meaning of the mysterious phrase ‘elbow grease.’ (“The Mystery of the Spanish Chest”)
‘No, no, you do not derange me in the least.’
‘Good gracious– I’m sure I don’t want to drive you out of your mind.’ (Dead Man’s Folly)
‘Perhaps some convivial idiot who has had one over the eight.’
‘Comment? Nine? Nine what?’
‘Nothing– just an expression. I meant a fellow who was tight. No, damn it, a fellow who had had a spot too much to drink.’
‘Merci, Hastings– the expression “tight” I am acquainted with.’ (The A.B.C. Murders)
And one of my favorite bits of banter with Japp:
‘You’re a pig-headed old boy, you know.’
‘You insult first my nose and then my head!’
‘Figure of speech, that’s all,’ said Japp soothingly. ‘No offence meant.’
‘The answer to that,’ I said, ‘is “nor taken.”’
Poirot looked from one to the other of us completely puzzled. (Lord Edgware Dies)
3. Offering drinks to guests. For a man with such a grasp of human nature, it is remarkable that Poirot continually offers his guests exactly the sorts of drinks that they find disgusting. It works well for humor, however: in the TV adaptation of “The Disappearance of Mr Davenheim,” attention is called to this trait by Poirot’s offering “something warming” to Japp, who accepts since he’s off-duty… only to be given a cup of hot chocolate, much to Hastings’ amusement.
A couple of my favorite examples from the books…
Poirot pressed his guest with refreshments. A grenadine? Creme de Menthe? Benedictine? Creme de Cacao?…
At this moment George entered with a tray on which was a whisky bottle and a siphon. ‘Or beer if you prefer it, sir?’ he murmured to the visitor.
Superintendent Spence’s large red face lightened.
‘Beer for me,’ he said.
Poirot was left to wonder once more at the accomplishments of George. He himself had had no idea that there was beer in the flat and it seemed incomprehensible to him that it could be preferred to a sweet liqueur. (Mrs McGinty’s Dead)
So it came about that at three o’clock of that same afternoon, Rhoda Dawes and Anne Meredith sat primly on their chairs in Poirot’s neat room and sipped blackberry sirop (which they disliked very much but were too polite to refuse) from old-fashioned glasses. (Cards on the Table)
The one astonishing exception to this rule is Poirot’s interactions with Ariadne Oliver. In one story, he says to George that “I never know what she likes”– and yet he goes on to provide exactly what she likes. On every social occasion, this is the case. Mrs Oliver also knows exactly what to offer Poirot as a hostess, unlike most of his other acquaintances. (I’m currently writing a short story featuring Mrs Oliver, outlining the story of the literary luncheon in which she and Poirot first meet, and this becomes an important plot point.) Her attentiveness is especially notable in Third Girl, and the scene is translated nicely in the television series in Poirot’s visit.
‘Chocolate? With whipped cream on top? Or a tisane. You love sipping tisanes. Or lemonade. Or orangeade. Or would you like decaffeinated coffee if I can get it– ’
‘Ah ça, non, par example! It is an abomination.’
‘One of those sirops you like so much. I know, I’ve got half a bottle of Ribena in the cupboard.’
‘What is Ribena?’
‘Blackcurrant flavour.’
‘Indeed, one has to hand it to you! You really do try, Madame. I am touched by your solicitude. I will accept with pleasure to drink a cup of chocolate this afternoon.’ (Third Girl)

Hastings is also much better on this point than Poirot is with others. When he places orders for drinks for himself and Poirot, he goes ahead and finds that creme de menthe (the episode Jewel Robbery at the Grand Metropolitan) or the cup of chocolate or the tisane that the English scorn.
I ordered two whiskies and sodas and a cup of chocolate. The last order caused consternation, and I much doubted whether it would ever put in an appearance. (“The Cornish Mystery”)
One might conclude from this that only Poirot’s closest friends have that proper mutual understanding about drink preferences. Otherwise, Poirot’s completely out to sea.
4. The Countess Rossakoff. It isn’t only that he knows perfectly well that she’s a crook, and yet eternally fascinating to him. He is also aware on some level that she has probably lied about her romantic past. The story “The Capture of Cerberus” is jarring to Poirot readers on this point– the great detective chooses to remain willfully blind about this object of his affection. It is a very rare move for Poirot.
Poirot objected, ‘Her life can surely not have been safe and dull as a member of the ancien regime in Russia during the revolution?’
A look of faint amusement showed in Miss Cunningham’s pale blue eyes.
‘Ah,’ she said. ‘A member of the ancien regime? She has told you that?’
‘She is undeniably an aristocrat,’ said Poirot staunchly, fighting back certain uneasy memories of the wildly varying accounts of her early life told him by the Countess herself.
‘One believes what one wishes to believe,’ remarked Miss Cunningham, casting a professional eye on him.
Poirot felt alarmed. In a moment, he felt, he would be told what was his complex. He decided to carry the war into the enemy’s camp. He enjoyed the Countess Rossakoff’s society partly because of her aristocratic provenance, and he was not going to have his enjoyment spoiled by a spectacled little girl with boiled gooseberry eyes and a degree in psychology!
5. Employee misunderstandings. As my memory has it, Poirot is not really depicted by Christie as someone who particularly misunderstands his employees. A couple of times, Miss Lemon or George surprise him with an astuteness that takes him unawares. In Hickory Dickory Dock, he is dumbfounded to learn that Miss Lemon has a sister. But this cute narrative from the episode The Dream, while not part of the books, does perhaps draw on some of Christie’s notes about Poirot’s hospitality-related blind spots.
Poirot: “But you have never complained before.”
Miss Lemon: “I’ve done nothing but complain for the last six months!”
Poirot: “No!”
Hastings: “It has been mentioned, Poirot.”
Poirot: “Kindly do not band together against Poirot!”

6. The Chocolate Box. This famous early case, cited by Poirot as his one utter failure of deduction, is one of those few “blind spots” to which Poirot himself has openly admitted. I hesitate to mention it, since it doesn’t really represent a consistent, recurring misunderstanding on his part, as to be a personality quirk. But there is another “blind spot” of Poirot’s at the very end of the story which does recur, serving to amuse Hastings and the reader.
‘Or no– remember it, and if you think at any time that I am growing conceited– it is not likely, but it might arise.’
I concealed a smile.
‘Eh bien, my friend, you shall say to me, “Chocolate box.” Is it agreed?’
‘It’s a bargain!’
‘After all,’ said Poirot reflectively. ‘It was an experience! I, who have undoubtedly the finest brain in Europe at present, can afford to be magnanimous!’
‘Chocolate box,’ I murmured gently.
‘Pardon, mon ami?’
I looked at Poirot’s innocent face, as he bent forward inquiringly, and my heart smote me. I have suffered often at his hands, but I, too, though not possessing the finest brain in Europe, could afford to be magnanimous!
‘Nothing,’ I lied, and lit another pipe, smiling to myself.