Neither of them were good enough. Aspas is back home at Celta where he's loved and Mario back to Italy where he was wanted. Neither are still good enough just because they scored a goal or two and took a good free kick.
And just for balance, plenty of good players have come and not made it here under different managers, not just Rodgers.
They are probably not good enough, however, what I saw Aspas do 2 days back, never saw him do that at LFC. Also, yes quite a few good players came and did not perform, but again, not as many as under Rodgers, the list is quite long for 3 seasons only if you think about it.