Suzuki Bandit 250 won't start.

[Laava]

There's a shitload of variables and without seeing your bike in person no one here will be able to help you.

This dumbarse I used to work with had an old Citroen and when it wouldn't start one day he asked; "Do you think the spark plugs fell out?"
So yeah, check that first.

[actungbaby]

i awlays turend my fuel tap of at end the day not sure why even on modern ones that
had vacum to run the fuel through ,
i whould undo the fuel drains and empty the bowls and check the spark plugs to see if there wet and clean them gap them . if bike running okay when its going may just be lack of use i heard this models like this also maybe needs tappets checked maybe
be there too tight on inlets

This dumbarse I used to work with had an old Citroen and when it wouldn't start one day he asked; "Do you think the spark plugs fell out?"
So yeah, check that first.