I work for an IT department with about 50+ developers. It used to be about 100+ developers but was cut because of the recession.

When our department was bigger there was an ambitious effort made to set up a special architecture group.

One thing this group decided to do was create our own internal logger. They thought it was such a simple task that we could spend recources and do it ourselves. Now we are having issues with performance and difficulty viewing the logs generated and some employees are frustrated that we are spending recources on infrastructure stuff like this instead of focusing on serving our business and using stuff that already exists like log4net or Enterprise Logger.

Can you assist me in listing up reasons why you should not create your own .net logger.

Also reasons for why you should are welcome to get a fair point of view :)