Compression test question for potential 912 purchase

[911C2S]

I'm looking at a car that has the following compression numbers:
1) 145psi 2)140psi 3)120psi and 4) 150psi

#3 is 10% lower than the others. Is this a problem?

I was told this could be the potential problem-
"The cooling air to #3cylinder is blocked by the oil cooler so it tends to run hotter and as a result it tends to wear faster than the other cylinders."




Any help is much appreciated.
Thanks