I think it's all down to motivation. We have quite a large team (16 DBAs) where you can see juniors (1-2 years experience) who are better than a couple seniors (10+ years experience) which just should not happen. They become complacent in their roles & yet can still probably find a new job quite easily by simply showing the duration of their CVs. This becomes even worse when looking at SQL Server since only 3 people support it (vs 15 people for Oracle). None of the 3 SQL DBAs are at the level of the good, mid-level Oracle DBA here, let alone the top Oracle seniors.