That's true for just about anything (cars, motorcycles, bikes, boats...). The advantage is that you can upgrade on the "installment plan", and upgrade only those components that you've learned (from personal experience) would make a significant difference, and leave in place those that may be less expensive, but working just fine. But it also assumes that I make a good choice in the frame out of the gate. It's interesting to look at the geometries of two bikes of the exact same model but different sizes. I can see that two riders of essentially identical proportions, preferences and riding style (a theoretical condition if ever there was one! ) but different sizes might come away from a test ride of the same bike with different impressions. It also seems to me that what may be fine on a one- or two-mile test ride (if the LBS allows even that much) might turn out to be problematic on a 25-mile ride.

I'm starting to think that maybe I should buy a used bike for my first roadie..