IME a lot of people who are what other people call ‘a success’ are driven by very high standards, insecurity, unhappiness or escaping from something… which makes me think striving to be ‘successful’ isn’t entirely a positive thing to do.
On the other hand, things I’ve done which have required a massive effort, or breaking through barriers, or I’ve done well at (rather than just participated), have given me such a buzz and sense of satisfaction, that I think ‘success’ is often well worth striving for – the rewards can be addictive. That’s when you get those moments of ‘life is brilliant’.
And somewhere in the middle you need to find your balance. I’m still on the journey personally…