One thing you sometimes here in IT is "there are no wrong doors", which I think is meant to mean that whoever the business contacts should be able to point people in the right direction to someone who can help. This all sounds very customer focused but you should be very concerned if you see regular walk ups as it is either because people don't know who they should be talking to or they do know and they're trying to circumvent the correct process to their own advantage. Both are probably indicators you haven't sorted out service support in your organisation, the business either wanders around until they find an IT person to ask a question to, or they have learnt that calling the Help Desk doesn't get them to the right people. 

Now many a technical support team has helped a walk up and felt good that they have been able to provide a good customer service, indeed many a manager has encouraged it in the mistaken believe that no wrong doors will get a positive response from the business, but many a technical support team has found that next thing you know they can't work on calls in the queue because of the barrage of people at their desk asking questions, trying to get priority or just wandering around trying to find the right door by trying all the doors. 

These days most IT Departments have a phone number you can call to get help, and a ticketing system to allocate calls to second and third level support. So far so good, but next thing you know the technical teams are swamped in requests and a lot of those requests are fairly trivial, not a good use of their time. The requests build up and next thing you know nothing happens fast, it sits in a queue for a long time and although there may be some concept of priority applied, often someone feels they are not getting attention fast enough and approaches the technical teams directly, further aggravating the problem as they now can't work on the calls they do have.

So how to get out of this spiral, well move the Help Desk from a "dumb" front end to a smart front end.

How to do this, well first and foremost get the service desk to have better information about the following things, The Service Support process overall looks like this