system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Why did the Empire phase out all the perfectly good technology from the Clone Wars?

In ROTS, specialized clone trooper units, multiple walker types, and perfectly functional Venator class Star Destroyers were all shown late in the film as belonging to the new Empire. Why did they eventually replace these with more standardized units when they could've kept them for different situations (ex. Venators as carrier ships)?
gpt
Cost-cutting necessitates standardization, and even with the assets of the Separatists seized, the Empire needed a way to pay its war debts.  When the galaxy is relatively at peace, there's no need for all that specialization.  

Besides, a lot of that older equipment was getting on in years and maintenance was becoming a hassle.  Contractors went out of business, parts became out-of-stock, the sort of thing that's given engineers and managers headaches since the invention of replaceable parts.  At some point, it's cheaper just to bring an entirely new vehicle into service than to keep fixing the old one.