Honestly? I worry that I will injure myself or get sick and not visit the doctor when I really should. I was raised with a “walk it off” mentality, and a couple years of broke, grad school life in New York didn’t really help that. I really only visit the doctor when I absolutely have to, and I worry about both overusing and under-utilizing medical care. Also, my mother nearly died about a decade ago because her appendix burst and she thought her abdominal pains might not actually be severe enough to visit the ER.
I also never replace shoes when I know I should. Shoes always feel like a frivolous purchase, even if I’ve worn holes in the ones I have.