It took me a long time, over 20 years to really accept this and act on it. Still, I do have too much small stuff. Sick trees I have no trouble passing up, but I have a hard time with passing up cheap. And I start way too much from seed. All major time wasters. Once I got a couple trees that were more mature in the ''becoming bonsai'' process, I discovered that there is a whole different set of techniques that you use for a mature tree, that you never get to do with sticks in pots. If you want to learn bonsai quickly you need trees at all phases of bonsai development. And not too many at any one stage. Exhibition ready trees need much more time to manage than sticks in pots. If you have too many sticks in pots, you won't have time to bring more mature trees to exhibition ready.