El Crapitan has so many problems it's ridiculous. They broke not only all kinds of Open Source software with their overly paranoid system protection, but also a

El Crapitan has so many problems it's ridiculous. They broke not only all kinds of Open Source software with their overly paranoid system protection, but also a bunch of hardware by messing up the USB drivers. There are now tons of musical instruments, Arduinos, and other USB devices that don't work with El Crapitan. Apple's response was: ... there was no response. Us hardware manufacturers are still looking for a fix. Our customers are angry at us and blaming us, and we can't do anything. There's no way for our customers to even tell Apple what's wrong, either.