Both aren't easy to do. Especially when we're talking habits or routines. When we are so used of those bad habits -- and doing it over again consistently, with or without conscious -- to break it takes more than just our mental effort. Sometimes even motivation or inspiration wouldn't cut it either, it requires more than that. We are talking sacrifices, endurance, preserverance and things along those lines.
Why bother? Anyone who works 9 to 5 obviously has a routine; anyone who prays 5 times a day has it too; regular smokers, does have one as well. In short, like it or not, we all live by routines and habits. The only difference is, what kind of routines or habits do we all practice.
ps: Me thinks breaking a habit is generally tougher than to create one. Maybe its just me.