Most devices are bogged down with bloated skins, apps, and other features you don't need.
Sometimes it's stuff from the manufacturer. Sometimes it's stuff from the carrier. Usually it's both. But the bottom line is all of these extras on top of Android bog down what normally would be a great smartphone operating system.
In the latest case, that crapware comes from Amazon, which will begin selling some unlocked Android phones at a heavy discount to Prime members but with a big catch - they'll come stuffed with ads on the home screen and your notification window. They'll also have Amazon Apps like Amazon Video preinstalled.
Amazon
Two of the phones Amazon will sell at a discount.
While the discount may sound appealing, it's unnecessary. There's no good reason to buy a phone at a discount if it means having to deal with ads sitting next to notifications for text messages and Facebook updates. There are several great unlocked Android phones already available on the cheap, and they come with minimal crapware.
Motorola's Moto G, which costs $200 unlocked, is a great example. So is the $400 OnePlus 3, which gives you a premium smartphone experience for half the cost of a comparable iPhone.
Cheap-but-good-enough Android phones have become so ubiquitous by now that there's no reason to compromise by selling a piece of your lock screen to Amazon or some other advertiser. Android has enough problems like dismal security and software updates. Don't add to them.