[jondubois]

Interview processes are more about social skills than technical skill (even in engineering interviews). There is a huge amount of randomness involved - Maybe the HR person just didn't like your face!

It's mostly about understanding the company culture, reading the interviewer's face and trying to figure out what they want to hear as you go along (of course technical skills are a prerequisite).

The only time I didn't get an offer was because I asked for too much money. I think asking for more money is a good idea though; it weeds out all the frugal companies.

I think that if your success rate is 90%, it means you're not charging enough. You need to bring the price up and allow the success rate to drop - Then the average quality of offers will go up.