Spellcast makes things easier for players by allowing infinite macros when you chose a spell from a menu, or by scripting your console to do things under specific conditions without you needing to take an action. This is the twin brother of the AFK Summoner.

What's funny, is that 4 years ago, players were much more careful about admitting to using Windower, because they got banned for using it even though half of Windower users just wanted to be able to Alt-Tab out of the game.