First of all, let’s understand the difference between, and just why manufacturers opt to change the stock Android experience in the first place. Stock Android, as you may well imagine, is actually your phone UI the way Google actually designed it. Ever since 2016, this has become much better thanks to Google shifting to what they called Machine language. So the benefits as you can well imagine are clear. A phone operating system that will actually work as Google designed it to, with an optimum functionality of most Google apps.
So why do manufacturers change it, or fiddle with it as users like to say? Why do they have terms like bloatware to describe the changes manufacturers make to the UI? The answer is actually quite simple.
In a market where over 90% of phones run on Android, a different UI remains one of the few ways to differentiate your phone from the crowd. And despite the hype against it, the evidence is hardly clinching when it comes to custom UI’s. Firms like Xiaomi, Huawei, and Samsung, which round off the global four along with Apple, have all customised their UI’s far more than most others and done none the worse for it.
Customizing the UI does have its disadvantages though, besides the obvious. For one, it might mean a longer delay when it comes to Android updates, as manufacturers need to do more work to make it compatible with their own changes. Speed, though not a massive issue anymore, does go down in some cases too.
Really egregious examples of bloatware, the sort Samsung was famous for till a year or more back, are coming down now, though with space and memory even on mobiles gradually becoming abundant, there is every chance that bloatware or custom UI’s depending on your perspective, will make a comeback again.