That's a good way of putting it, and it gets to a key difference between open source and proprietary software.

In the open source world where a million eyes make all bugs shallow, developer hours are thought of as free. So if you change something it's no big deal because all the developers using your thing can simply change their code to accommodate it. It doesn't matter how many devs or how many hours, since the total cost all works out to zero.

In the proprietary world, devs value their time in dollars. The reason they're using your thing is because it's saving them time. They paid good money because that's what your thing does. Save time. Get them shipped. As a vendor, you're smart enough to realize that if you introduce a change that stops saving your customers time or, worse, costs them time or, god forbid, un-ships their product, they'll do their own mental math and drop you for somebody who understands what they're selling.

In the end, all we're talking about here is the end product of this disconnect in mindset.