Some of them actually make sense, but most make NO sense at all.
Doing my French degree at university I always had trouble remember genders. A French guy in our flat told me it was easy - to them the object seemed to take on feminine or masculine characteristics, according to its grammatical gender.
"So how can a bike be
un velo
or une bicyclette, or a car be
un auto or
une voiture?"
"Don't be difficult!"
Even worse in German and Russian. Like Latin they have neuter as well.