Right, but if it requires maintenance, and it doesn't bring in enough money to cover the costs of that, turning it off might be more cost-effective than doing the maintenance.

Look at Google Finance, for example - uses Adobe Flash, which is 2 years away from EOL. Presumably it's not making any money and doesn't have a maintenance budget; if it did, they'd have moved away from Flash when the iPhone came out. But when Flash hits EOL, maintenance is mandatory.

Turning it off is what I'd do in that situation.

This is exactly what everyone thought about Reader, and Wave, and Picnik, and Revolv...