One CEO’s method of avoiding long emails she doesn’t have time to read:
“I also always say to my team: ‘Please don’t write me a novel, I won’t read it.’ I just don’t have the time. Instead, write in the subject line what it is that this is about. And tell me upfront–is a decision needed, or do you need me to look at something, or is it a ‘When you have time, take a look at this’?–so I can prioritize effectively and be responsive when I need to be.”
Source: Life Would Be Better If We Added This Line to Every Email