Any logic to this strange phenomenon?

I've just been to check on my fennel seedlings. They are in a 40 cell seed tray insert.

Almost every cell around the perimeter has a good healthy seedling in it, but none of the ones that are not at the edge have any sign of activity in them. Not a single one.

I definitely put seeds in every cell, and I used the same compost throughout, and the seeds all came from the same packet.

The laws of probability and quantum mechanics say this is not only possible, but given infinite amount of attempts, it a certain to happen sooner or later, but it's still very strange.

 

Maybe something to do with it being dryer around the edge?

 

I can't explain the erratic germination when you plant in a cell trays , but when I plant seeds in a small prop I sometimes get erratic germination . I know how to sow seeds fairly evenly , and not too dense . But some germinations leaves me wondering why one quarter of the seed tray shows no germination or the centre does not germinate etc etc . I do rotate the trays regularly and move them around to ensure the light and heat is distributed as evenly as possible. So why these erratic patterns

 

Something that needs to be considered, imo, is that it can be quite easy to over-water, the result being poor germination