Comment 35 for bug 1047384

pitrou:

No, the main concern is not that it will force people to use simpler passwords, but that people will install, without being aware of the layout issue, then on first boot be locked out, not understanding why, and having to re-install or re-format loosing all their data.

Which is what happened to me at first, and one of the reason why I completely stopped to use Linux (and it used to be my main OS for years)