What are the infuriating issues that should be inconsequential, but are still maddening enough to have you cursing even the best motor? 
I recently drove a Vauxhall Corsa VXR. This is a great example of a brilliantly fun hot hatch that was tarnished by one small fault.
The Recaro sports are a great asset to the car - they're supportive, comfortable and generally brilliant. Untill you flip them forward to let someone into the back, and then attempt to get back in.
At which point you find yourself squashed between steering wheel and seat back whilst attempting to carry out a manoeuvre that would fox a Shaolin monk, just to reach the seat controls.
This is a small, and you would imagine simple thing. But a great car that's ruined by a small irritation is akin to finding a short-black-and-curly in your lobster thermador.
If it were a bad car overall, it wouldn't matter. It's not even like it's a new fangled idea - a Citroen Saxo has seat memory as standard, as should be the case with all three-door cars.
Factory sat-nav systems that don't have full postcode entry is another way to infuriate. Even worse is door handles that feel like they're going to break if you open the door against the wind.
No matter how much I try to fathom why you would decide to put flimsy door handles on a Civic, origami seats in a Corsa, or sat-nav without postcode entry into an S-MAX, there seems to be no good reason.
It can't be that hard to sort these things out. Can it?