It's partly a religious thing, partly what you're used to and partly using the right tool for the job. Some programmers use debuggers as a crutch and some compl

It's partly a religious thing, partly what you're used to and partly using the right tool for the job. Some programmers use debuggers as a crutch and some complex systems (e.g. that involve multiple distributed components or are timing dependent) can't be easily debugged using traditional debuggers. EDIT: yet another factor is sometimes you may not even have access to the system you need to troubleshoot. Being able to reason about code execution without observing it is a useful skill (and still a debugger is a useful tool).