These are some examples of tasks you will not be able to do with alerts disabled: moving someone to another group, promoting or demoting a host, creating a table chart, cancelling registrations or possibly making a donation. Basically, if you click this box, it will seem like Ministry Sync just broke for you.
To reset alerts, all you need to do is quit your browser and reopen it. After you do that, alerts will start popping up again and this time you won't click that evil little checkbox, right? ;)
Unfortunately, there is no way for us to hide this box. So the only thing we can do about it is to tell you not to click it.