Why are budget e-bikes are harder to maintain?

[Justin]

For most people, lower-priced models are very attractive. However, one common issue with low priced ebikes is getting spate parts, it is very difficult to replace parts locally. Even simple repairs can be very annoying when you cannot easily find components. Parts in lower price models aren’t standardized.
So you think you get better long-term experiences with premium brands, or do you believe budget models are fine if you keep it well maintained?