There is no key to success. It is a combination lock!
Jeff Haden has nicely pointed out the different numbers that one needs to put in place to make good progress in one's professional life. His opinion that experience is irrelevant while accomplishments matter a lot is somewhat bold, and perhaps rightfully so. In addition to being better indicators of success, accomplishments are a great way to motivate your future self. Instead of thinking that you'll take up some job to get more experience in the field, you should be thinking about what amazing products/artifacts you can create during your time there. This will help you focus on being more productive and less complacent - landing a nice job is great, but a waste of opportunity if you don't do anything worthwhile.
Distancing yourself from causes of your own failures is a dangerous thing. You might end up years later, still in denial, thinking "I've done everything right, but somehow it never works out" - and if you then decide it's not worth putting in your best effort anymore, then it's all downhill from there on.
For everything you do, there is a good way and a better way of doing it. Of course, it's for you to choose your battles. One simple test is to introspect from time to time to see whether something you are doing really excites you or not. For the things that you are truly passionate about, going that extra mile will immensely boost your sense of achievement.