Really, why did he?

We see in the prequels (and even more so in the EU) how whenever a Sith becomes weak, he gets killed off by his own kind. One example is the Apprentice who becomes more powerful than the Master. Or as we can see in SWTOR trailers, Darth Malgus kills his badly injured master.

While the situation may be reversed here (it's the apprentice injured, not the master), we saw how Palpatine easily gave up Count Dooku simply because of this age, although he was a very powerful Sith.

And now it becomes clear that Darth Vader would no longer be able to become as powerful as the Emperor predicted because of his injuries (which indeed is the case: although foretold by a prophecy to be an extremely powerful Force user, losing his limbs cuts off of Vader's powers and abilities).

Doesn't it make a lot more sense for Palpatine to give up on Vader and find a new, more powerful apprentice?

Really, why did he?

We see in the prequels (and even more so in Legends) how whenever a Sith becomes weak, he gets killed off by his own kind. One example is the Apprentice who becomes more powerful than the Master. Or as we can see in SWTOR trailers, Darth Malgus kills his badly injured master.

While the situation may be reversed here (it's the apprentice injured, not the master), we saw how Palpatine easily gave up Count Dooku simply because of this age, although he was a very powerful Sith.

And now it becomes clear that Darth Vader would no longer be able to become as powerful as the Emperor predicted because of his injuries (which indeed is the case: although foretold by a prophecy to be an extremely powerful Force user, losing his limbs cuts off of Vader's powers and abilities).

Doesn't it make a lot more sense for Palpatine to give up on Vader and find a new, more powerful apprentice?