We said this in the early days of Ember. Specifically, that while we were still making a lot of changes to Ember before 1.0, that we were going to go to strict

We said this in the early days of Ember. Specifically, that while we were still making a lot of changes to Ember before 1.0, that we were going to go to strict SemVer compatibility post-1.0. This made it clear to early adopters that things were rapidly changing, so you needed to be comfortable with that. It also helped people understand why there was so much breakage leading into 1.0, because it was in service of a much more stable post-1.0. Since 1.0, we take Semver pretty seriously, and I think the strategy of being pretty unstable pre-1.0 in service of a very stable post-1.0 has paid off.