Daniel Kahneman is a psychologist that is famous for studying judgement and decision-making.
When he was working for the Israeli Air Force, he observed the flight instructors would criticise the cadets rather than praise. Their reasoning was when a pilot performed badly and received criticism, their next performance would usually be better. But when a pilot performed well and received praise, their next performance would usually be worse.
Kahneman noted this phenomenon was a simple reversion to the mean – overtime, your level of performance is an average of all your performances, so when you do really well or really poorly it’s more likely your next action will be closer to this average.
So if your level of performance is determined overtime, do you think it’s better to sustain praise or criticism?
For Kahneman, the proof is in the research. Go for positive feedback.