Comment 6 for bug 930148

@zzecool There's testing that was done which shows empirically that intellihide confused users who were new to Ubuntu. You can read more on that and the decision to remove it here: https://lists.launchpad.net/unity-design/msg07665.html

We can't be sure that users will get used to something which will likely confuse them off the bat, because if it's not obvious right away, they might be inclined to give up on it and go back to whatever OS they were using before. We certainly don't want that, and we can't force users to try to figure out their interface. Not everyone is skilled enough with computers or patient enough for that. That's why the default is always visible, so they always know where it is.

The reason autohide can stay is because it is considered an advanced feature. If they are so inclined, they can find the autohide option in System Settings, where the options even describe how to reveal the launcher and give additional settings. By this point, the user should be sufficiently informed as to what's going on when they let the launcher hide, so they're not left wondering where it went. And if they find it gives them issues, they can always reach System Settings from the power cog and reset to the always visible default.