bad weather - Neah, I just drive when it rains
road safety - Pretty good infrastruture where I commute
flats or other mechanical failures - PITA more than a concern.
violent crimes - My commute is a low crime area, but Sharon Tate lived in a low crime area too. I don't worry about what I cannot control.
thefts - No
hassles to dress up upon arriving for work - I can slide on the bike clothes sometimes.
being late to work - I'm salaried, and can make it up staying late
Pretty lucky that I pretty much have no worries other than forgetting my winter gloves on one of those mornings.