General upon-arrival sweatiness; there's no way I'd be able to cycle in if I couldn't shower when I got there.
Tiredness - a cross-town commute, whilst enjoyable, can get pretty tiring by the end of the week, especially if you're doing long and intense hours in-between the riding.
Clothes. I'm fortunate to be able to work in clothes that are back-packable, but if you're in a suit everyday I imagine it gets a little more complicated.
Fear of 'Cycling in London'; some people just aren't very comfortable on bikes. Or they're fat. Or both.
I'd add when you have alot to carry / alkward stuff. Lots of things are easier to move on public transport.
If you are catching a train from central London on to somewhere else, then unelss you are well outside of peak hours you can't get a bike on board.
Being able to read a book.
A couple of panniers (I know not cool) can carry loads of stuff, taking something large on PT @ rush hour is just a pain.
Regarding rain. It's raining
Shower, dressed, walk to bus/tube stop, wait - getting wet. Get on full damp tube, get off, walk to work, sit down in same clothes.
Get up, out on bike, get wet, shower, clean dry clothes, sit down
A couple of panniers (I know not cool) can carry loads of stuff, taking something large on PT @ rush hour is just a pain.
Regarding rain. It's raining
Shower, dressed, walk to bus/tube stop, wait - getting wet. Get on full damp tube, get off, walk to work, sit down in same clothes.
Get up, out on bike, get wet, shower, clean dry clothes, sit down
I know what I prefer