From concept to actually producing something of value I would say 3-5 years is actually pretty normal. But that takes into account that ICO's are like venture capital. To make that long term worthwhile massive profit potential needs to be there as you have an opportunity cost to each ETH you put towards an ICO.

Lately that opportunity cost has been very high. Any coin that hasn't increased in value as fast as ETH shows this opportunity cost. You had the opportunity to just hold ETH and profit from it's run up.