The point in the year when black heels actually earn their spot by the door is that stretch from September through to the dark end of December, when every other week seems to bring a dinner, a leaving do, a slightly too formal dress code you didn't choose. Daylight disappears early, nobody can see your shoes properly after six anyway, and black just works with everything you own without a second thought.
The difference between a pair that lasts and one that lets you down shows up fast, usually within the first hour. Cheap synthetic uppers crease across the toe within a few wears and never recover, whereas a leather or good quality leather look will soften and mould to your foot instead of just giving up. Check the lining too, a lot of the disappointing ones skip it entirely and you feel every seam by the end of the night. The heel itself matters more than people admit, a covered wood or metal core stays steady, while the hollow plastic ones have a slight wobble you only notice on cobbles or a pub floor with a dodgy tile. Stitching round the sole should be even, not glued on in a hurry, and the sole edge should be finished properly rather than left rough and pale where it's been cut.
A decent pair ages well if you let them. Leather takes a shine and a crease pattern that's genuinely flattering after a few months, and a tiny bit of cream polish every so often keeps it from drying out and cracking at the toe. Suede needs a brush rather than a wipe, and if you get caught in the rain, stuff them with paper and let them dry slowly rather than near a radiator, which I learned the hard way with a pair that came out looking like they'd been through a hedge. Keep them in a bag or box rather than loose on the floor of a wardrobe, because dust and scuffs from other shoes do more damage than actual wear. Where they fall down is anywhere you're on your feet for hours without a break, a long shift, a wedding where you're stood for the ceremony then dancing till midnight, or any walk longer than you'd normally do in trainers. They're also the wrong call for daytime in bad weather, a wet pavement and a leather sole are not friends.
Where they suit best is anything with a bit of occasion to it, an evening meal, a work do, a christening, a date where you want to look like you tried without announcing it. They go under trousers for a smarter office day, under a dress for something after work, and they're the one thing in the whole wardrobe that never looks like you're trying too hard, whatever the season.