I think having a dad who was into mechanics is a good influence, but I recall getting into bike mechanics around the age of 10, after getting a racing bike for my birthday. Looking after my bike was fun and interesting, but I grew up in a small village with miles of fields between things and so it also meant that if I didn’t learn to look after it, I would have to walk.
Later on in life, I came across this quote that, "If you find a job you enjoy, you’ll never have to work again." and so this became my focus for some years. I was very much into philosophy, theology, nature, art; those kinds of things and loved long distance walking. On a return trip from one said walk, I came across some old thrown away bicycles. I could see at least one good bicycle among all the parts and so took them home and got to fixing up a new bike, which got me into long distance riding.
This all had me getting back into my old hobby of maintaining and modifying my bike and noted that when I was working, time seemed to stop and was more like a meditation than any work. Then one day met a guy selling parts on Gumtree, who had a load of retro bikes he wanted restoring for a project of his. This soon became a friendship and I found myself slowly transformed into a bicycle mechanic. It was quite unexpected, though on reflection quite natural and somehow cyclic!! ;-)