Designers were probably thinking "well this is stupid but it's what I'm paid to do and I didn't decide to have a fucking bed be always online". The execs that made the decision are probably thinking "why didn't the designers think of this problem and prevent it? We should fire some. "

The designers were thinking "we want to force users to a monthly subscription".

So against my preference, we bought one of these. Years ago and it wasn't so crazy expensive and the basic 'cloud' functionality was free. Over the course of the years of the initially decent warranty, the covers sprang leaks and so we got free upgrades carrying us all the way to a generation of the product where they replaced the crappy molded leak prone water mat with decent tubes that seem to be more resilient, all without needing to get in the subscription. As a consequence, I know about their evolution.

From the onset, they were hammered with "phone over the internet control is bogus, add a remote or buttons on the base or something", and they kept responding with vague "we are working a solution". Well, they ultimately did, they added earbud-style 'tap N number of times on the side to adjust things or dismiss alarms". Ok, super awkward and still no buttons, but at least it has local controls, right? Well, I go to try it and it just gives the long-buzz error indication. Turns out the app has to be used to activate the bed or schedule a start time before the local controls will let you control it. When they explicitly added a local control loop, they blocked it from working unless the cloud service said it was ok.

This is not "crappy developer stupidly doesn't know how to make local control work". This is "developer going out of their way to screw over a customer to force them to keep paying for every single month they want the product to keep working".

A shame, aversion to buttons aside, the hardware design is really quite good, quiet and effective and seemingly more leak resistant.

but what were the designers thinking?

"We need to remind them who's in charge."