Not all fallen leaves belong in compost --
Fallen leaves are full of nutrients but should they all end up in your compost or on your garden beds? The answer is "no." Source matters. A lot. Those leaves in the gutter and on the street can be easy to rake up but consider them off-bounds. Pavement and gutters catch (1) over-spread fertilizer, herbicides and pesticides as well as (2) the run-off from recently-treated yards and sidewalk strips, (3) vehicle fluid drips and leaks (antifreeze, oil, brake fluid), (4) lead tire weights, and more. Put street and gutter leaves out for yard waste collection (there are good reasons to keep them out of our storm drains and water ways).
So which leaves can you use? Leaves that fall on your yard and garden beds are just right. You can mow over the leaves when you mow your lawn. Now you have grass clippings and chopped leaves which can can be spread on garden beds, added to the compost, or left on the lawn to break down slowly over winter, protecting and feeding the soil. Chopping the leaves up a bit helps them break down faster and release their nutrients. It's still true that a thick layer of whole leaves or leaf mulch is hard on a lawn so don't overdo it. But do use those leaves right where they grew. After all, your soil provided the nutrients to grow the leaves. Why not hold onto those precious nutrients and recycle them back into your soil?