Sieves can be a pain but if you've used it just for dry ingredients, a good rinse after the wash and allow it to dry seems to work.
Can't say any particular item stands out. Worst things are bits that were never originally on the item getting on it as I remove it from the water, bits pretending they weren't removed after I went over the surface many times and visually inspected it, so it has to be redone and hard water that leaves stuff over all as it drains/dries. Almost badly enough to force use of a teatowel.