If software vendors were accountable for flaws in their software, then the main point is no longer how secure the software is, but who gets the liability.
What would happen if an important flaw was found and exploited in Android? Google makes it (based on Linux) but charges no license fee for it. If it turns out that the phone maker gets the liability, that would make a very compelling case for using Windows instead.
Heck, it would make creating a brand-new mass-marketed piece of software pretty much impossible for any startup. You cannot be absolutely certain that a piece of software doesn't have bugs, and if you're not a big corp, the first lawsuit will simply kill you. It doesn't even have to actually be your fault; people who misused the software will still sue you and before it's settled you'll be dead anyway.
Knowing that you're at risk of sudden death from circumstances beyond anyone's control, commercial customers will stay away from you. And if you make a mass-marketed device that runs OSS, and a single flaw is found and exploited in that OSS, you're similarly screwed; you can't get back at the OSS maker because they don't sell it. Better use Windows instead; lots more flaws, but I'm not paying for them.
Is that what you had in mind?