I've worked with some designers who were coming right up on what's typically 'retirement age', who were basically still individual contributors, but just at a v

I've worked with some designers who were coming right up on what's typically 'retirement age', who were basically still individual contributors, but just at a very high level. They bring an incredible wealth of experience – everything we think is new has probably been tried at one point before. But the best ones don't take a jaded "we tried that already" view – they're just able to riff-off the new ideas while sharing insights and learnings over an incredibly long time window. There's being physically young, and then there's having a 'Beginner's Mind', which is something that one can have at any age – or never grasp at all.