Yeah, @corawilliams, I was the same until ours saved a big job.

Oh man, @blair626, I feel that so hard. Was it one of those red shop rags that just blends into everything? I once spent a full hour looking for a tool I swore I left on a cart, only to find it wrapped up in a greasy rag I'd tossed aside. The panic when you think something is just gone is the worst feeling.

That dirt trick from @uma_baker99 is a game changer for color matching. I did a patch on my old brick walkway and it looked way too new and clean. Sifted some of the sandy soil from the garden bed right next to it into the mortar, just a handful. The grey tone went away and it finally looked like it belonged. What kind of material were you fixing, concrete or brick?

Gotta disagree with @graym49 here. A sharp eye won't help when your car battery is totally dead in a dark parking lot. You need the actual power to start the engine, not just to see the problem. Relying only on observation leaves you stranded.

My uncle's barber tried the same thing last summer. The hair just formed these dense, wet mats that blocked all the air. It really does seem like a total waste of time and compost.