We need them.
Time set aside each month to create a recovery buffer: giving your body a chance to catch up from the previous weeks of hard training.
The alternative, training both hard and long, is a tempting shortcut; but one we rarely get away with.
Deloads: either we choose to take them, or our bodies choose them for us.
Rule of thumb: set aside one week of every month to cut the volume in half. Keep the intensity up and try as hard as usual, but only do half as much total work.