I was doing my lessons and was pressing the buttons that I know a certain word (either a bit, a lot, etc.) and wanted to know if I will see the word again somewhere else or depending on how well I know the word will it show up in a different place/time.
It is still part of your schedule, it just has its mastery level pushed up a bit (or a lot), so you do not have to study it as much. They will still come up in the future :)