We've all called a customer support line only to get told that 'due to high call volumes, waiting times may be long'. As frustrating as it is for customers, it's even more frustrating for support agents at the receiving end of an irate client's tirade (I have been there countless times). Another source of frustration is hearing (or saying), 'Please bear with me, our systems are (always) slow.' This is an example of bad capacity planning and a lack of research for sure.
From an IT manager's perspective, just keeping operations running smoothly is an art in itself. Things can and do go wrong in IT systems. It's not enough, however, just to keep on 'putting out fires'. Being able to forecast, predict and plan for future IT capacity requires intelligent planning, research and orchestration.