What constitutes a draft bust?

Unless qb a first round player should provide a significant contribution in the first year.
2nd year he should start and stand out
If this does not occur the pick is not a bust, however, if he does not contribute significantly by his second year the team did not get the value they should have from their first round choice.
A bust does not contribute in two years. Even if he plays but does not make an impact, I would consider it a bust.