i'm sure for forcing people to do the unpaid labor of reviewing papers they are not experts in, which they do not have time to properly read, or write up notes for because they fear blacklisting will only lead to better published work! surely this is good for science!
We all have periods where we need to say no; I said no twice this week. The policy is three nos, not one 'no' damns you forever; it says editors 'reserve the right' to consider not 'definitely will reject'. On avg, editors know who is a good citizen but cannot in a moment, vs who always says no.