How to change order of add-on event order and when it might make sense

In SAP Business One - Add-on Administration you have the option to define the event order of add-ons.

For example, here B1 Usability Package is last, but if you highlight it and press the up/down arrows you can change the order:

The reason you might want to do this is if you have multiple add-ons that collide in their event order, and you want to have one do its work before the other.