I originally picked it up as something to just play with around the house. a number of gigs later (as a solo artist and sideman) and now it's something I'm known for and take pride in my continual learning.
Started at 58 after I retired. I wish I had started sooner but working f/t and having 6 kids. I don't know if I would have really found the time to play and enjoy my uke. I probably would have felt guilty, like I should be doing a chore.
I first got one for my 7th birthday, but learned informally from my dad and did not really take it seriously. By 10 I had abandoned it for guitar, piano, and bass, all of which I failed miserably at.
In my early 40s, I picked up the uke again, and this time it took, and there's been no looking back. Maybe by the time I'm 50 I'll even been good at it