A computation model doesn't have to be Turing complete to be useful in practice. Consider a language where all programs must halt - all loops must be bounded, a

A computation model doesn't have to be Turing complete to be useful in practice. Consider a language where all programs must halt - all loops must be bounded, and recursion is not allowed - you can still solve a lot of problems with a language like this, but you cannot say, run Brainfuck, as such a language is not Turing complete.