I would invite friends to try DDO if there were no guild decay.
I have a very small guild, 6 active accounts.
I do not want any more people in the guild because it would make it more difficult to farm for renown.
Before I play, I farm for renown decay.
As the decay goes up, time spent playing for fun goes down, and my resentment of the system goes up.
Renown in DDO does not mean fame or reputation, it means OCD.
It means finding the best quest time/chest/difficulty combination and number of accounts to get the most renown.
I have run the giants vault 500+ times; it is no longer fun for me.
There is one thing that could make the giants vault fun.
Turn guild decay into a monster with a heart that could be ripped out, greased, set on fire, and eaten as a tasty ham.
I tried the new system several times and found it more confusing than the current system.
I just gave up after a while and figured I'd wait for the wiki to explain it.
Iron defender bugging out... after buffing it.
Getting logged out while typing this.
In other words, Guild Decay is simply a pointless repetition.
Summary - I would like to have casual players in my guild without having to spend extra money or time grinding for renown... and grinding for renown isn't fun.