Testing Coronavirus Vaccines and Getting the Shots

Oddly I find myself being confused about the vaccine.  If I were approached to participate in Phase III test of a vaccine, I'd likely agree.  Why?  It would be a contribute to the safety of humans.  That's good.

But when the vaccine has been tested and released, I won't be the first one to get it.  Why?  For the same reason I wouldn't rush to buy version 1.0 of software.  That's not particularly logical.  The Phase III trial would have identified any known side effects and proved its safety otherwise.  It's possible that there might be rare effects that are found only when millions, not thousands, are vaccinated.  (There was a flap in the 1970's over a flu vaccine, but it seems that after some years the fears weren't well founded.) 

The difference is that in the second case I'm acting mostly in my own interest.  The community will benefit from my being vaccinated, but that's a minor benefit compared to my participation in the trial.  So the risks to me of being vaccinated are the same in either case.