At least one Commissioner was forced to resign already, after being accused of collusion with organised-crime, under President Barroso. One Commission President (Romano Prodi) was somewhat marred by accusations of widespread corruption towards the latter part of his mandate (iirc generically aimed at various Commission members and nominees, rather than himself, but still there were demands for his dismissal from various governments), saw his powers effectively curtailed, and his chances of a second mandate were wiped out.

Traditionally, nothing in Bruxelles get done without widespread consensus, including staying in power.