I think it depends on who the redesign is for.

If it's for the customers, I don't see any reason to think it would. I would even expect it to be reverted if hated.

If it's for the devs (so they can do busy work and get a promotion), I think it is a sign of weak leadership and a harbinger of eventual doom, these are generally hated but ultimately tolerated.

If it's for the shareholders, I think these are the redesigns the really kill websites.

Cory Doctrow talks about this here: https://pluralistic.net/2023/01/21/potemkin-ai/#hey-guys

"enshittification" is the name for this concept that results in this behavior that we see.

> Here is how platforms die: first, they are good to their users; then they abuse their users to make things better for their business customers; finally, they abuse those business customers to claw back all the value for themselves. Then, they die.

The redesigns always scary the final users because they have to learn again how to obtain information or how to use effectively a service (think about a municipality website). I do not think every redesigns kill the website, but you need to be very cautious about editing the workflows.

There is a lot of similarities between redesigns and general software development

- The bigger the change is the harder it is to effectively migrate dependant users/systems/apps

- The bigger the scope is the harder it is to maintain feature parity with the old version through the development window

- The less researched the rationale for the change to users/systems/apps is the more likelihood it will cause them problems

- If you mess up the implementation you are doomed

Hence the best practice to introduce incremental well researched changes to actively used systems in a systematic way.

With a web redesign, there is uncertainty in the way users will respond of course. But tbh ive seen APis with far more unpredictable responses :P

As always, it depends. Sometimes the design misses the point of the original site and makes it harder to use for the folks already there. These tend to go over badly, since people would often rather leave than learn something completely new (and often less efficient).

But I've also seen examples where the redesign goes well, usually because it maintains the general 'feel' of the original while making it look more modern/easy to use.

A site going offline after a redesign is likely more the case where it was hoped a redesign would provide a lift in engagement, but didn't solve what the core problem(s) were. A redesign in the face of glaring problems can however accelerate the demise where the users become aware of how out-of-touch the maker/operator is or has become.

From my experience redesign of UI of anything is usually bad for end users. But I don't have statistics so just a random opinion.