I don't know if this is true, or if it makes sense, but...
It initially seemed some people hadn't changed at all. Instead various people have changed in various ways.
Categories included: what a person has [including wife, kids]; what activities a person does [racing, dog shows]; job.
The problem is that I haven't changed significantly in those. My category is maybe best described as: changes in how I categorize myself. Which is a completely internal, mental masturbation kind of category.