The picture below was sent to us by a customer who has installed his new faucet just a few days earlier. He complained about the debris in the faucet. If you look closely, you will see it is construction debris. When he remodeled his kitchen, he disconnected the supply lines from the valves at the wall. The valve opening was pointing up. They installed the supply lines, the valve was full of construction debris, which he did not remove. When they turned the water supply on, the particles were blasted into the faucet plugging the aerator, backcheck valve, and cartridge.
You should always cover supply lines during construction and thoroughly flush the water supply lines before turning on the faucet.
