People are being disturbed on a regular basis; sometimes it’s justified, but usually it’s not. What many do not realize, or worst, ignore, is the cost of disturbing someone and the chain reaction it creates.
Some reasons that they think it’s alright to disturb others can range from lack of prioritizing his tasks, vague definition of an emergency amongst colleagues, incapability of managing clients demands, etc.
Someone disturbed during the execution of a task loses momentum and concentration requiring 5 to 15 minutes (give or take) to get it all back depending of the task/person.
For example, a developer, right in the middle of analyzing an algorithm for a software’s functionality will completely lose his train of thought, and have to redo the thinking from scratch. That will cost him time, may make him forget an idea, and the probability of him making an error rises after being disturbed.
So let’s say this developer loses 15 minutes when disturbed, and is disturbed twice during a day. That adds up to half an hour of lost time per day. Assuming out of the blue he is paid 30$ an hour, that means 15$ per day is wasted for this resource. That means 75$ per week and about 3750$ within a year! Just imagine the wasted money if this spreads across an entire team.
Believe it or not, that’s a detail compared to the chain reaction it creates. The reality is, this developer as a “to do” list to accomplish, his time is limited, and managed by project managers who share this resource’s time. Meaning, the developer couldn’t carry out all his tasks because of disturbance, so the project managers will have to adjust project/resource schedules which means even more time wasted.
Now some will think this is exaggerated for disturbing someone for one minute, well, that is because the impact of “unconnecting” and “reconnecting” to a task is underestimated. I’ve once worked in a chaotic environment where I was disturbed every half hour; at the end of each day, I could barely remember half of my day because the rest was wasted left to right.
Disturbance is destructive to efficiency, make sure people around you know the cost of disturbing others so that it’s being done only when justified.