Why was female succession a problem in Tudor England?

Female succession was considered a problem because it was believed that a woman could not hold the crown against the factions plotting to seize it. The Tudor reign was frought with pretenders and challengers for the throne. The monarchy was historically passed down through male offspring.... princesses were bartered and married off for political gain.

Henry VII took his crown after the battle of Bosworth Field. His claim to the throne was not a strong one, but his marriage to Elizabeth of York solidified his claim. The York and Tudor dynasties become one, as he'd successfully married a woman who had a stronger claim to the throne than he did.