1. TV advertisements that say things like "eliminates up to 100% of dandruff flakes" or "up to 100% grey coverage" - typically ads for shampoo and the like.
Like, I can defeat up to 100% of ninjas by doing nothing, since "up to 100% of ninjas" means "x ninjas, where 0 <= x <= the total number of ninjas". A building could be up to 100% demolished by throwing a large rock at it, which is to say that it will be only very slightly damaged. Saying that a shampoo removes "up to" 100% of dandruff is saying nothing.
Stupid wishy-washy meaningless-statement-making assholes.
2. People who stand at a pedestrian crossing but don't hit the button, presumably on the assumption that they will automatically get a green light and the button does nothing but tell them to wait for the scheduled light change which would have happened anyway (which is only sometimes the case).
There are some crossroads where the pattern is like:
(A) west turning south cars only (and pedestrians crossing between NW/NE or NE/SE if the button was hit in the previous A, B or C),
(B) east and west cars only,
(C) north and south cars only.
If a pedestrian hits the light switch on the northwest, northeast or southeast corner, then they can cross at the next A.
What happens about 20% of the time, is that one or two plonkers stand at one of the lights and wait until A, upon which they still don't get a signal to cross because they never hit the button. Then they frown in confusion and eventually jaywalk at the next opportunity, cursing the system. Or you arrive at the crossing, mash the button and grimace at them, having watched them stand there like a muppet for about 30 seconds and miss the crossing timeslot.
Dumb. If you're standing in front of the button, just fucking hit it.
3. People who cross a road and casually hit the button as they walk past, even though they're not going to wait for a crossing signal. Instead, cars and cyclists have to stop and wait uselessly for nobody to cross, since the guy who hit the button is already out of sight, back on the pavement.
If you're going to just cross the road anyway, DON'T hit the fucking button!