Bicycle and scooter are two simple non-motorized modes of private transportation. Each has its advantages and disadvantages, and in the end it comes down to a trade-off of usability and storage.
It's not surprising that bicycle is by far the more convenient mode to get from point A to point B. It is also better equipped to handle inclines, and has the better stopping mechanism with the brakes. The biggest drawback of bicycle is storage. Point B as a destination may or may not have convenient storage of the bicycle. Despite locks, bikes secured outside are not immune to damages from other people or the weather.
Scooter is the alternative to the storage issue, given that it is relatively easy to pack it in a small unit that can be carried by one hand into facilities like restaurants, which would not be able house a bicycle. However, on average the scooter may go only half as fast as the bike. It is also slowed down much more on upward inclines, and tires the leg (the standing leg in particular, not as much for the kicking leg) much more.
What are the implications of the trade-off of usability versus storage? Bicycles have comparative advantages in longer trips, while scooters have comparative advantages in shorter trips. There is no cutoff distance, as it will vary for each person's strength, the terrain of the path, and the surroundings of potential bike storage locations, but 1-2 miles serve as a reasonable estimate. For those more physically-fit, costs of using scooter is lowered. Smoother terrain will benefit the scooter, while inclines benefit bikes. Finally, of course better storage options benefit bicycles.
