I needed transportation to and from my first duty station after boot camp. Couldn't afford a car. So I bought a then-new 1976 Motobecane. Started riding just for the 20 mile round trip commute. I disliked running but still had to do the twice-a-year physical fitness test, so riding helped.
Next thing I knew I was hooked -- racing a few crits and time trials, long distance rides with a club. I was never any good at racing but had fun.
I quit riding for 30 years after the service. Started riding again in 2015. Took forever to get back into shape. Hooked again.