Personally the biggest things that effect bud growth imo, are proper feeding levels/ good environment, lots of light, and the genetics. Ofc everything ties in together , thos are the main things tho.
Gotta remember just cause someone gets good genetics out a pack dont mean you will , not so much variation on fem seeds however normal seeds , you might have to pop a shit load to find the crem dela crem genetics.
I bought a pack of acopolco gold ages ago , must have popper like 20 seeds only 1 was worth a toss , even then i eventually got rid of it as it wasnt up to my standard.