Competition is fierce. Most start out working on their (startup or music) product part-time until the product becomes popular enough that it is a "hit". At that point the entrepreneur may be lucky to end up funded ("signed") which will help their ability to pursue their product full time and spend the marketing dollars to reach a larger audience.
Thankfully it's unlikely the VC/entrepreneur relationship will become as twisted and exploitative as the major music industry's relationship with artists as being funded does not suddenly unlock access to an entire set of verticals inaccessible to unsigned artists. Or does it?