My PPL instructor in the early nineties was obsessional about checking the flaps and detents (PA38) before take-off.
Turns out he lost a mate to a major dose of asymmetric flap pretty close to the ground.
Never talked about it much so don't know the details.
But It rubbed of on me: I allus give the Arrer (mechanical flaps) a firm test of the detents during the pre-flight..
Safe (and symmetric) flying
Cusco