Invitation to the interview is based on a weighted score, if i recall correctly. They take your scores from the UMAT for eacsection 1: section 2 : section 3 in the following ratio 1:1:0.5
You then have to reach a threshold score of 149 or thereabouts to get an interview.
So technically you could do well in sections 1 and 2, bomb out a bit in section 3 and still manage to get an interview with a lower percentile. Similarly, you can blast through section 3, do well in section 2 and screw section 1 up a bit, get a higher percentile but not get an interview