I suppose it is very bad software but very useful and popular is that the people who create it concentrate on "business value" instead of "beauty". This means t

I suppose it is very bad software but very useful and popular is that the people who create it concentrate on "business value" instead of "beauty". This means that it solves specific problems very well but the overall architecture has become inconsistent and there are many weird quirks. Usually this is resolved by a complete redesign of the software that gets delayed forever, never becomes production ready and eventually disappears into obscurity.