Or your board op might get sick. What colour gel goes into it. What direction is it pointing in. The Board Operator needs to be very familiar with the lighting equipment prior to plotting the lighting cues for a production. This will enable full concentration on the creative designs being made rather than worrying about how to make the gear work.
Operation can be very simple eg flicking a light switch, or it can involve more complex equipment.
Student Theatre has a number of manuals for its ATOM in the office. It is very important to make sure whatever effect is achieved in the plotting session is able to be recreated exactly every night of the performance . Similarly, all actions taken to operate the board must be noted down in a clear manner enabling someone else to take over the show's operation if necessary. A plotting session can often take 5 - 8 hours. This means the show can simply be reloaded should any interference occur.