It's not about age it's about risk/reward. A youngster has nothing to lose if it starts a 1000 hour project. In the worst case scenario it will be a very good

It's not about age it's about risk/reward. A youngster has nothing to lose if it starts a 1000 hour project. In the worst case scenario it will be a very good resume that will get him hired. For an experienced professional that is already making good money from it's current job/business and has a family to sustain, losing 1000 hours on a project that can get him 0 in return is simply not viable most of the times. So youngsters are much more likely to experiment more.