If you're ten percent off with each bike line, it looks almost perfect. If you're ten percent off with each line while trying to draw a specific person, it won't even resemble them.
A caricature is one thing, and might be doable by an average person, but knowing how to do a caricature is a skill all by itself. A portrait is extremely art skill intensive.
I agree with that, but that’s just the difference between drawing a specific person versus drawing any bicycle. I suspect if you wanted to draw a bicycle that was recognizable as a specific type or brand of bicycle, small differences would be important.
A caricature is one thing, and might be doable by an average person, but knowing how to do a caricature is a skill all by itself. A portrait is extremely art skill intensive.