"Needs to apply themselves"

Question

Please help me figure out the meaning of the sentence "Needs to apply themselves" in the following text from the description of the app Clusterduck:

You will see that every duck comes with a playful personality description, such as, “Sometimes leaves the fridge door open. Needs to apply themselves.”

Here is a description of the game from Apple App Store:

CLUSTERDUCK is about hatching as many ducks as possible. As more ducks hatch, the more strange things happen. The ducks begin to genetically mutate! With each generation of ducks that hatch, the chances of things going horribly wrong increase at an alarming rate.

Answer 1

This is a stock phrase from school reports - ie, the document filled out by teachers at the end of a term to summarise how the child has behaved and what they achieved during that period.

"Needs to apply themselves" means that the pupil is not achieving their potential, because of lack of effort.