A little interruption may not seem like a problem, but the time sunk into getting back up to your “cruise altitude” is a huge loss of productivity.
You may not think that a minute here, or there, is a problem, but when you have to reset and find your bearings again you lose focus, energy, and time.
When you have a steady cruise with minimal interruptions, you will find that you feel more rested, get more done, and even have time to focus on yourself, and personal hobbies as a result.
There is nothing wrong with stepping in to help, as long as it’s worth the time, and doesn’t become a time vampire.
Learn when, and when not to take that call, or answer that text because it may be the difference between an important project getting done on time, or not.