Assume that one of your paper is not that good but however you don't see how to improve it.
How bad should be a paper such that it should not be submitted to a top 3?
The rate of acceptance is less than 10% so tons of not good enough papers are submitted (and the same applies to 2nd tier journals). A submission has a cost in terms of money, time and eventually reputation. A rejection could have the benefit of good insights from referees.
Is it then always worthy to submit to a top 3 journal?
My question is general, but I'm particularly interested in the case of a very young scholar (fresh phd or just phd student).