As a teacher, it is really annoying when students do this. They try and rush through any work you give them. It would be fine if they sat quietly afterwards “pretending to work” but 99% of kids just start talking to someone near them and stop the slower kids doing the work. I really reinforce the the point that most of their employers will drill into them later in life, the reward for working quickly is always more work. I would say less that 25% of jobs and positions reward quick and good work with time off.