What we have is a huge slush pile, 98% of which will prove worthless in the end except as a practice exercise for its creators. (Which is valuable, of course, just not valuable to the customers.) Because the bottleneck is the market. That's where the culling happens.
Like the majority of screenplays, most products are dead on arrival because they can't be effectively marketed. That is in part because the marketplace is crowded, but again: Don't mistake the stacks and stacks of App Store offerings for a saturated market. It's just a market choked with weeds.
One of the things the world needs is better software markets. The fact that you can't hear people screaming about their terrible software, or see and count the money that they would potentially pay for better software, is a sign of the market's ineffectiveness.
