I always say people have five productive hours per day. I ask they give me four of those on working days.
This applies to creative work: development, document writing, content production and similar. Meetings, sales, email and other types of interactions are less taxing.
I don't mean to downplay the effort of interaction-type tasks. It's the result of observing people around me. I know many people who are happily productive on sales for 12h workdays. I know no developer who's proud of code written on the 12th hour.
Don't assume that these sales people are so happy to work overtime. They probably rely on commission and/or need to hit that sales target. Sales teams are known for super-competitive, target-driven, and high-pressure culture. We software engineers have it easy in comparison.
This is a personality characteristic. For me, meetings and sales are definitely a production that tax me enough. I want to quota how often I do them. (Sales, preferably never.) Some people get positively powered up by sales or meetings though.
I’ve even had medications turn meetings and such social interactions around for me. So I know it’s not a universal truth one or the other way.
This applies to creative work: development, document writing, content production and similar. Meetings, sales, email and other types of interactions are less taxing.