Success Formula

idea + timing + plan x execution 
= reaching the target

idea + timing + plan (set of initial assumptions) x execution ((volume & speed x validating assumptions - failures) + (volume & speed x validating learning based new assumptions - failures)) = reaching the target

The key element of this formula for success is the multiplication between idea, timing and plan AND execution (x) ie. the team and efficiency of processes. If execution is zero, there will be nothing. The higher the execution volume and speed are, the better the likelihood of success is.

See Startup Development Phases framework to learn about creating a successful business and What is a startup? - page for visualization of most crucial key quality factors.