[Someone]

With iPhoto, you can easily move your photos elsewhere, but moving the metadata with it (what photo is in what album, recognized faces, etc) is another thing.

I call that a form of lock-in.

[prawn]

It creates/enables inertia rather than locks you in, I think that's what they're saying.

[ryanmarsh]

Inertia a.k.a. reasons for people to like and therefore stick with your product. How dare they.

[prawn]

No, it's clearly different to that, and to pure lock in. (And I wasn't offering judgement either way, just trying to help explain the other comment.)