Having to insert the plastic room key in a device beside the door in order to operate anything electrical, sometimes even including the air conditioning. What if you want to leave something recharging while you go out to lunch? Extra penalty for turning off the in-room a/c when a guest checks out so the temperature can go up to 80F or higher; such fun for the new guest not to be able to turn on the a/c and go out for a while.
Rooms where insertion of said plastic room key causes all 8 (!) lights, plus the television, to come on automatically. It's lovely to spend 30 seconds wandering around, turning off all but one light, every time you return to the room.
So-called air-conditioned hotels that really are not, because the "chilled" air is so warm the room won't even cool off overnight.
"Design" hotels with features and fixtures selected for looks rather than functionality, such as a bathroom lavatory set in the middle of a very large round countertop with no adjoining wall to keep items from falling to the floor. Who wants to lean way forward to brush his teeth at a lavatory set 6" from the edge of the countertop?
Rooms not cramped for space that have a bed-side table and/or light on only one side of a bed intended for two people.
Rooms, again of adequate size, that have no raised surface on which to place a suitcase, other than furniture that might be damaged or soiled by a wheeled suitcase.
Rooms with only 3 or 4 coat hangers. I don't care what they look like; just give me some coat hangers!
Rooms with no lavatory stopper.
Rooms with inadequate curtains. There's a reason most of us sleep at night. Or try to.
Balcony doors that can be inadvertently locked by pressing a small, unnoticed button.
Hotels advertising an elevator without clarifying that some rooms still require going up or down a flight of stairs, so potential guests don't realize they need to request a room accessible by elevator when booking.
Hotels advertising Wi-Fi that don't have adequate equipment to supply the service in all rooms. I don't care that you're fully booked. You know how many rooms you have; that's what you need to support.
Stairs without handrails, especially when poorly lit.
Hotels and restaurants that purport to be completely non-smoking but cater to smokers without limiting them to specific rooms or areas.
Museums covered by city passes or museum passes that charge the full regular plus special-exhibition fee when there's a special exhibition, not just the special fee.
Sale of water in ludicrously small (0.2-liter) bottles in restaurants, especially when it's over 90F outside.
Customers and railroad ticket booth personnel who complete their business transactions and continue conversing about personal matters for 10 minutes, while the customers in line miss their trains.
Whew. I guess that's enough. I feel better now.