I bought a set of tires. Installation included a free alignment check.
The cost of an alignment was substantial. I told the manager to call
me if he thought I needed one, and tell me what his check had measured.
He seemed baffled.

When I picked up the car, he said the alignment checked out, but I
should bring the car back in a few weeks in case it had gone out. I
asked why he thought it would go out shortly after a check. I didn't
get a convincing answer.

Is a free check a gimmick to sell an alignment for a car that's within
specs but not perfect? Maybe he thought I wouldn't spring for an
unnecessary alignment on top of the cost of the tires, but I might be
convinced later. How do you get a reliable check?