So This is a great question that I have no real answer to, just theories. Lots of old breeders will swear that good drug varieties have smaller seeds. I'm not so sure about that. It seems to me like the seeds are smaller with indoor bred vs outdoor. I've got lots of seeds that have been bred for generations indoor and they always are small, while the outdoor seeds seem larger. Back in the early 90's we used to get a lot of outdoor bud from Oklahoma and Arkansas. It was mostly skunk and Afghani. From what I could understand they were grown and bred outdoor for 20-25 years. The weed was fire and had "popcorn" seeds. Some was totally seedless, but most just had a few seeds. Occasionally the bud would be loaded with seeds and was 5 to 10 bucks an once cheaper. The amount of seeds never mattered. It always had the huge popcorn seeds. The mexican bud we used to get also seemed to have large seeds. So all in all to me it seems outdoor tends to be larger in general and indoor seeds are smaller. Regardless, if you have a plant that's getting continually pollinated seeds will be at different stages of development. That's just my 2 cents.