The pros are used to it. When we drive into the lumberyard to pick up a load of two-by-fours, we know that part of the job will be checking them for bad splits, bows, warps, knots and damage. And the same goes for everything else we buy. So if you're buying materials for a project of your own, check everything over before you leave the store.
An example:
A customer recently picked up a screen door from one of the big box stores, but when we went to install it, we realized we were going to have to take it back to the store.
Notice how there's a lot more of the bottom board showing on the right than there is on the left. Something's not right here.
Turn the door around, and we find the problem: a screw missed its target, splintering part of the frame...
...and forcing the main panel out of place.
Most stores will let you return defective products, but of course it's a lot quicker and easier not to buy them in the first place.
Thanks,
New Hampshire Construction