Which one would you value more?

I'd be ok with 2, maybe upto 3 rounds. Anything more than indicates indecision to me

I'd say better way - contribute to open source, get noticed, have 1 interview with CXO to validate culture fit and get in

10 is just not acceptable...2-4 would be good

One solid interview is pretty hard to pull off. from the company's POV, I feel 2-3 interviews are needed to judge the person from multiple aspects.