Even on the research side, I think I put more effort into code maintainability than some of my associates. I'd like to think I bring a moderating, high-level design influence to what might otherwise be a mess of low-level, hand-optimized C code.
To be honest, I've come across quite a few people who write their code that way because it means that only they can maintain it. Keeps them valuable and employed.
Code should be written in a clean, readable, maintainable style and to an agreed set of standards.