There's a non-trivial portion of population that is familiar with the concept of having products fit to them personally: made-to-order uniforms, glasses, other

There's a non-trivial portion of population that is familiar with the concept of having products fit to them personally: made-to-order uniforms, glasses, other sorts of assistive products. I find it surprising that this is less common than it was in the past, and that people are more willing to put up with something that’s a subpar fit for them. One tech example that would benefit from custom fit are in-ear headphones. It would make sure that product is a perfect fit for every customer every time, rather than roughly every single customer having to put up with a suboptimal fit and poor comfort.