Exactly the same reason why I like it! It doesn't sound as harsh as
Lucille, and it doesn't remind me of my mom's soap operas like
Lucinda (which I like, but still). And as a plus, it's not used very much anymore.
I hate
Lucy, too, and I can't come up with any nice ways
Lucilla would be shortened.
Luce and
Cilla sound strange to my ears.