This is a given in any sport or career. The reason I say that is because some people are simply just weak links. They have the confidence at the beginning but they eventually just give up and quit.
You most likely have met or possibly even been friends with people who are weak links. From the very beginning they were not all in. By all in I mean they lacked the passion. The passion to keep going when times got tough.
Everything that I have done in life there have been these types of people. From skateboarding to now design I have met many people whom just gave up and did something else.
This could also be in relation to what Robert Greene said in regards to people getting bored with a profession. Because if you get bored with something how likely are you to keep doing it? You will eventually stop and find something else to do.
The same type of example is when you are in a relationship with someone and everyday becomes routine. You will eventually get tired of it or just deal with it and find what ignited the spark in the beginning.
So therefore as I come to an end with this post do your best to not start anything you are not going to stick with. If you are not going to give it %120 then don’t even waste your time honestly.