How it usually goes:
1. Have an idea
2. Do about 3 of those things:
- sketch out a few diagramms of how it would work
- think of a name and buy the url
- estimate what you would have to buy and what it would cost
- make a project folder
- lean back, imagine life after the idea made you rich and famous
- write about 2% of the required code
3. Get distracted or don't have time to work on thr idea
4. Have new idea, repeat from 1