20 years next to grandad and their WW2 era CRM gets a bit tedious.
I'd hate to be in the back of a 380 at QF or in the right seat of a 330 purely for this reason!
Pilots by their very nature are ambitious and their comes a time when you need to flee the nest and taste the rewards and challenges of being a commander.
None of us joined an airline to sit up the back or in the right seat forever.
I'd happy with anything under 12 years.