It
is an excellent question!
I’ve personally been through this scenario where my bike manufacturer bit the dust and vanished. The reality is that even if the motor isn’t proprietary, most vendors are making proprietary electronics or combinations of components. E.g., there’s no standardization for the wiring or the controller programming… The list goes on. There are some de facto standards in the e-bike world, but mostly in the “analog” stuff like brakes, shocks, etc. The electronic parts of the drivetrain are not sufficiently standardized, nor are the communication protocols for fully controlling the bike. People that build their own bikes use programmable controllers, displays, and can pick and choose batteries to use as well. But, generally speaking, you have to go with a specific manufacturer (Bafang, Bosch, Shimano, etc….) even if you’re doing it yourself.
So, in my case, when Juiced Bikes went belly-up, I bought a (exact same) spare bike and have collected spare parts. I’ve still got my bike running after a year and a half without my bike company existing, but there are some single-sourced components that I cannot replace. Right now, if my battery dies, I’m SOL.
I can’t speak for
Velotric, but my advice is this. If you’re willing to become a bit of a shade-tree mechanic and horder, sure… go ahead and buy direct. Otherwise, buy from a local bike shop (LBS) that supports your brand.
Oh, I will add that this site has a lot of knowledgeable folks and can often help when something needs fixin’. Youtube often has vids of folks dealing with similar issues.