What age would you consider a kid to be a "failure to launch" scenario?

I had an interesting and delightful discussion my son’s friend last night and I gave my strong opinion that if a kid reaches 25, is not going to university, is not struggling with some disability and is still at home then it is clearly a failure to launch scenario. I was pretty vociferously told that this was not such a scenario by all the guys at the table.

What is your opinion of when a kid has overstayed his/her cushy family home?