Why is this happening?

I have absolutely no insight knowledge, but I think it's not a bad assumption to have that, it's costly to run the models, when they release a new model they assume that cost and give per user more raw power, when they've captured the new users and wow factor, they start reducing costs by reducing the capacity they provide to users. Rinse and repeat.

They're "optimizing" costs wherever possible - reducing compute allocations, quantizing models, doing whatever they can to reduce the cost per token, but vehemently insisting that no such things are occurring, that it's all in the users' heads, and using the weaseliest of corporate weasel speak to explain what's happening. They insist it's not happening, then they say something like "oh, it happened but it was an accident", then they say "yes, it's happening, but it's actually good!" and "we serve the same model day by day, and we've always been at war with Eastasia."

They should be transparent and tell customers that they're trying to not lose money, but that'd entail telling people why they're paying for service they're not getting. I suspect it's probably not legal to do a bait and switch like that, but this is pretty novel legal territory.

There are frequently claims that Anthropic is somehow diluting or dumbing down models in some subtle way. Unfortunately it’s tough to validate these claims without a body of regularly checked evals. This test set should hopefully help settle whether Anthropic is actually making changes under the hood or whether the changes are all in people’s heads.

It’s entirely possible it’s not happening, and this phenomenon of “model degradation” is just user hype meeting reality.

https://www.anthropic.com/engineering/a-postmortem-of-three-...