This task is one we think about occasionally when we notice the gutter is overflowing after a good rain. Let's start with some of the negative aspects of leaky, clogged gutters.
Clogged gutters can cause water to backup into the house and lead to wall and ceiling damage.
The wood fascia around the house can rot by water backing up from clogged gutters. If you can not see the need for two cleanings, then it is best to clean after all the leaves have fallen in late fall. An electric blower can blow out the material gathered in your gutter. Wetting down the packed areas perhaps an hour before starting the cleanup will loosen the caked material and help with its removal. Hang a bucket on the ladder, to hold your cleaning tools.