Had a Cessna full up with friends and thought the climbout was anaemic to say the least - friction lock not on and the throttle had vibrated out... I often forget to put up flap up after takeoff and I've even almost forgotten to put the gear down when I was overloaded on a checkride (no less)... And this is when I'm in practice and have flown recently
When I get my plane back from annual next week I immediately need to fly a xcountry 2 hrs to get it back home. After the test flight (to see that everything works properly) I'll make sure to do a couple of circuits to nail the visual references, speeds, etc before I set off.