Do you only use serum when you're "older"?

So I was on pinterest (lol, I know) and there was a debate in the comments about serum and only using it as you "get older". Some of the commenters were saying it's only meant for when you're middle aged and others were saying to use it daily even if you're a teenager.

I've used serum on and off over the last three years and I'm in my late twenties and it's been mixed for me so it's not an active part of my skin routine. Some of them are too sticky, others seem okay.

What are your thoughts? Do you feel serum is targeted to an age bracket or can we use it whenever? Personally I dont have enough knowledge on serum to make an opinion so I'm asking it here.