For me it's not so much taking risks as it is crossing things off my bucket list. I want to die not regretting that I "should have done" something. Unfortunately, my bucket list is empty so I'd better add more stuff to keep me going, such as seeing my very young grandkids graduate from college and being here for some great-grandkids.
I will admit that I never got on an airplane until I was about 60. At that point it was "well, I'm going to die someday anyway" and flying was about the only way to complete the bucket list. The best part is that one of my items was to dive in the Caribbean. Now I've done that a bunch of times. Also, I just did my second Manta Ray Night Dive in Kona--it was better than the first time. Another big factor to consider is that at 60 these things became possible because I was no longer supporting my kids, have very few bills, practically no debt, and can do whatever I want with my money and if I should get killed my kids will still be able to eat and pay their car insurance.