Procrastination is the avoidance of doing a task which needs to be accomplished. It is the practice of doing more pleasurable things in place of less pleasurable ones, or carrying out less urgent tasks instead of more urgent ones, thus putting off impending tasks to a later time.
Procrastination comes with all sorts of labels around it to justify its existence and the slow the inevitable - the performance of an impending task. I'll do it tomorrow or next week. I'd rather draw this now instead of the commission. I'll just watch this next episode and then start painting. Etc., etc., etc. I know, because I do it all the time and if I am not careful a day can be wasted and no meaningful art is created. This can cause stress and increase deadline pressures and make my job as an artist not as pleasant.
Procrastination is about time management. We all have the same 24 hour period to fit activities, meals, exercise, recreation, sleeping, etc. into. What we make room for shows its level of importance in our life. And how disciplined we are in sticking to a time allotment, once we truly want to do something makes a big difference.
Procrastination in art students tells me a lot about how serious they are about learning. If homework was "forgotten" or they were "too busy" to practice guides me in understanding whether they want to remain hobbyists or take art to a more accomplished level.