In my line of work, I write a lot of Windows services. For me, logging isn't a luxury; it's actually my only UI. When we deploy to production, we lose access to debugging and even the databases to which our services write and without logging we would have no way of knowing any specifics of issues that arise.
Having said that, I do believe that a concise logging style is the best approach. Log messages tend to be limited to the business logic of the application such as "received message from account xxx" than "entered function yyy". We do log exceptions, thread starts, echoing of environment settings and timings. Beyond that, we look to the debugger to identify logical errors in the development and QA phases.
