Breeders talk about “unstable genetics,” meaning that a seed’s origin is unknown. Make sure that when you buy a packet of seeds that it or the breeder who produced them can list where the seeds came from and how they were crossed and/or backcrossed to get the seed that you hold in your hand. If you can’t get a seed’s history, it could be anything and the result of poor breeding practices.
An inexperienced breeder might cross a male and a female one time and sell the resulting seeds as a new hybrid strain, but professional breeders usually put their strains through several rounds of backcrossing to stabilize genetics and ensure consistent plants that reflect those genetics.