Why does Cary Audio keep discontinuing good amps?

Is this to keep us buying from them? Why not upgrade good designs?
A large manudacturer makes amplifier 'X' that has an appeal to a finite number of folks who buy them. After the initial sales period the demand is reduced to a trickle, so the manufacturer has two options, 1)Bring out something 'new' or 2)Bring out a revision/upgrade/improved version.

When a company has produced an outstanding design it will often offer improved versions relying of the rep of the original version to encourage sales. When the company has produced an ordinary product it will come out with a 'new' design and rely on sales from its overall rep for producing interesting products.

Cyclonicman is right - this all makes little difference so long as the manufacturer remains in business and is will ing to service their stuff (and you do due dillegence re the products actual performance before you buy).

The idea is to actually dump the amps once they met the expense building them. After paying off the cost of the production run and having made some money the remasining amps are free to them or as some might put it just gravy.
On the hand if they have a real winner they don't mness with it, For insrtance the SLP-05. You and I can probably get it for a few bucks off listat Upscale but not 40% off. Of topic kevin dfeal takes a really fair msrp will tell you that all he has is the Jaguar special paint edition with the kopndo platiunum in bonsia olive tree oil and paper made by hand that he personally winds Caps plus ther se , ex, sq, mods . all of this was custom made for his store atthe cary factory and obviously it ends up costing 100% over the or in reality a few grand more than the plain one. No unmodded are available. In addition since that is a very appealing preamp I watch the price and Mr. Had keeps raising it.
So even Cary will hang on to to a hot seller. In the current economy the days of preamps that cost that much are over. Thank goodness he still has some plain AE-3s for $550.-
when a company starts moving away frome the ,,made in america brands ,they seam to be looking for money insted of build .Most of cary products have went from point to point wire, tubes to solid state gear .and when china makes there products they move forward in technology.I dont even know if cary has service for there old stuff.THe pre pros sold an the dacs come from china .nothing like that made here .I think cary went west on his stuff.and if he comes out with a american made amp it will cost alot
Which amps? Solid state amps or valve amps?

The valve amps seem to be upgraded regularly - CAD-211C became 211AE and now 211FE. Same with the CAD-805C.

The solid state amps might be EOL'ed thanks to the end of a transistor run. Transistor manufacturers tend to make batches of these - if demand remains high, they will make more batches. But if a transistor does not sell well - once the batch sells out, that's it. You can't get any more. Cary might have run out of stock of a particular transistor, forcing a redesign and thus a new model.
I don't think they just kill off amps on a regular basis. The v-12 went through three iterations: v-12; v-12.I and v-12R. If I'm not mistaken, the v-12 in its various forms was in production for over ten years. I believe the CAD120 is doing the same thing with the newer II model. Both great amps, btw.