i don’t really understand how this whole us visa process works: my girlfirend was denied a visa, re-applied after two days and got it. this is also when i found

i don’t really understand how this whole us visa process works: my girlfirend was denied a visa, re-applied after two days and got it. this is also when i found out certain forms have extra pages full of required details that only apply to females, not males. the whole process seems extremely random