Drivers carry the additional burden of potential legal action from passengers in case of an accident.

Carpooling combines many of the disadvantages of public transportation (lack of privacy, not on-demand) with the disadvantages of the automobile (low safety, high fuel consumption).

Tends to be rather complicated to organise seriously and are difficult to keep together, due not least to changing travel patterns and needs.

Any appointments or other things someone in the carpool has to do will make the other person/people in the carpool have to wait, or will make the schedule drastically change.