IT: You are your own worst enemy.
As an IT professional, work tends to be very repetitive, which means that you will often be doing the same thing again and again, which leads to laziness; that is, a tendency to stop following the checklist or procedure and to do things from memory. This can lead to problems. It is said that necessity is the mother of invention. Within IT there is a similar saying: Laziness is the mother of invention. Laziness in this case is the mother of automation.
Automation is an important tool in the IT arsenal. If a task is to be repeated regularly, it should, to the greatest extent possible be scripted. Then that script should always be used to accomplish that task. That leads to operational consistency, which should be the goal of any IT group.
The type of task which necessitates scripting will be different from company to company, but a simple look at the tasks being repeated regularly should quickly enable you to find the operations within your organization, which should be tackled first. One of the most common is configuring new machines from the OS on up and updating configurations across the board.
There are many systems which will allow systems to be built up rapidly and accurately as well as enforcing their configuration to a known baseline. Two that come to mind immediately are puppet and chef; both of which are open source configuration management tools and both of which, in a short amount of time, can make sure that all of your servers are built and remain configured to exactly your specifications.
If you are not using one of these configuration management tools, or something similar, you are not only making your own life harder, but you are making it more likely that something will go wrong.