Butters, go buy World of Warcraft, install it on your computer, and join the online sensation before we all murder you.
--Cartman: South Park
ATTENTION FANS: I will be played by James Barbour in the upcoming musical, "BroadwayWorld: The Musical."
Simon Russell Beale, John Lithgow, Joseph Marcell, Michael Pennington--all really good actors with very different styles. I think it's great that we have options to see different takes on the same play. As others said, you don't have to see all, or any.
"You travel alone because other people are only there to remind you how much that hook hurts that we all bit down on. Wait for that one day we can bite free and get back out there in space where we belong, sail back over water, over skies, into space, the hook finally out of our mouths and we wander back out there in space spawning to other planets never to return hurrah to earth and we'll look back and can't even see these lives here anymore. Only the taste of blood to remind us we ever existed. The earth is small. We're gone. We're dead. We're safe."
-John Guare, Landscape of the Body
Obviously there were a lot of great minds thinking alike on this and other gluts of this sort, but part of what precipitates it is that it is a play that sells both to audiences and perhaps more importantly to actors of a certain stature.
But when there are several high-profile productions all occurring in the same season, you're risking splintering the audience base. I would wager that most theatregoers are not going to go see more than one production of King Lear a season- it's a long piece and there is very much of a sentiment of "we've just seen that" in theatregoers, regardless of quality of the production - which means they will choose based on loyalty to either the producing theatre or the star.
"...everyone finally shut up, and the audience could enjoy the beginning of the Anatevka Pogram in peace."
I don't disagree with your reasoning, but obviously these duplicate productions are being produced on the basis of some other reasoning, which you can either explore or ignore. It's really no different from asking why some artist who is repeatedly associated with flops continues to get work.
I will never forget the Mabou Mines production done at The Public (when it was under Joanna Akalatis' tutelage) and Ruth Maleczech played a female Lear and the play was set in a garbage dump landfill (Lear was the owner of the landfill, this was her kingdom). It was bizarre to say the least. I think a third of the audience walked out and the rest just stayed to see if the production could get any worse.
There's also the itsy-bitsy consideration that Lear is one of the supreme works of literature, English or otherwise. We're lucky to have had the opportunities to have seen this masterpiece in our lifetimes.