Why does Rhino have lots of issues in filleting complex surfaces while Solidworks usually fillets easily?

[eobet]

Throwing another “why does Rhino have issues filleting simple surfaces” on the stack:

Having Fillet Issues - Pretty New to Rhino

Hello, I am a student and I have been trying to learn Rhino for a bit now but there are still some things that I am having trouble with… Currently I am trying to make a custom restaurant booth and I need to soften the curved edge to make it look softer like a cushion? I hope that makes sense. I am trying to use the fillet tool but when I do it doesn’t fillet the solid it only makes a new surface… It also curves into itself at the top and it’s not supposed to. [Booth Issue] I know there are s…