There is no such thing as a "quick question." When someone asks you a "quick question" it's quick to ask, but not quick to answer.
A quick answer would be: yes, no or maybe, but the fact of the matter is, just because it's quick to ask someone a question, doesn't mean that it is quick to answer the question.
Those quick questions usually require you to look into something and to spend time not doing something else. They require thought and processing. They require you do stop what you're currently doing, which may be hard to get back into doing.
And each time a worker was distracted from a task, it would take, on average, 25 minutes to return to that task. To perform an office job today, it seems, your attention must skip like a stone across water all day long, touching down only periodically.
Here's a quick question: how much do you spend on food each month? How many times have you gone to the gas station int he past 5 months?
Those questions are quick for me to ask, but require some time to answer.
Every time someone asks you a quick question, there's an opportunity cost associated. Quick questions are poisonous to productivity and are rarely ever "quick".