There have been some worrying tales about poor results in the UK. My first one was a tad shy of perfection for the reason I stated but when I heard some of the correction needed after some UK ops I was very glad to be where I was. (in both senses.)
Worried I'd muddled the issue, I phoned a friend.
Yes. The ciliary muscle is like a torus surrounding the lens, and attached to it by means of radial filaments. Muscles cannot extend or expand, they can only contract, and the ciliary muscle is no exception. The lens "wants" to be thick to have a short focal length. When the ciliary muscle is relaxed it pulls on the radial filaments and flattens the lens, and thus increases the focal length. Contracting the ciliary muscle allows the lens to get thicker and focus on near objects.
With age, the lens tends to lose it's ability to recover its "thick" shape, so you cannot focus on close objects.
You can see how this goes against old concepts and why the aged tome (something like) 'Better sight without glasses' is based on muddled thinking.
That book has been going so long you have to interpret the 'old English' a lot of the time.