Why do merges sometimes go the wrong way?

All of my name merges are well-researched, and I believe that IMDb know this, as most of them go through okay.

However, sometimes they are merged in the wrong direction.  This has always happened.  Sometimes I am able to go back and send them the right way again.

I currently have one 230529-212250-324000 which went the wrong way, and I have twice attempted to move it back, the first time with one piece of evidence, the second time with multiple evidence.  However, IMDb is refusing to action it.  
230531-125218-483000
230601-230955-679000