My crazy, astigmatic eyes have always made glasses expensive, so I have always just worn a previous pair of glasses for cycling. My distance and mid-distance vision is fine with them, and they work well enough for reading the closer up speedo. Another old pair goes in the car in case something happens to the pair I'm wearing. And another old pair goes in the shed by the bikes in case I go for a very casual ride to the grocery store or something close.
I used to carry clip-on, flip-up sunglasses for the sun, but a previous hobby with photography had me wishing to see everything "unfiltered" and I realized I don't really need sunglasses like I used to.
Because I have the extra pair in the car, and carry my "everyday" pair to the office with me while commuting in my main "bike" pair, I always have a back-up, should something happen to the pair I'm wearing...although now that I think about it, I haven't broken a pair of glasses since college, 40 years ago.
I'll also mention that I wear old-fashioned tri-focals with the small insert at the bottom, rather than transitional multi-focus. When I got my first pair of transitions I realized that the multi-focus extended out to the sides as well limiting the area of distance focus in the periphery, which was a problem biking and driving. I am much happier with all-distance on the sides where traffic comes at you fast, especially on the bike.
I will say that transitional lenses do offer a focus for every distance, but from what people I know say, that area is thin and requires a lot of head-tilting to find it, although sometimes I think that would be nice to have, but over-all I'm happy with what I do.
Just sharing.