Mephisto, they secure a strain by breeding it over the coarse of years to stabilize it and get the bad ruderalis traits out of it. Then they plant something like 300 or 600 seeds of that strain and abuse them. From that they take the top 4 and do it over again A few times before they finally sell the seeds. This is why autos have become so popular recently. They are doing things that was never done in the past. Like yoda's google search. Autos usually stay below 2' tall spindly growth. That's in the past for the most part.