People stick to the same tube routes to get around. This means, companies who advertise on the tube are advertising to the same people, over and over again. They may get plenty of exposure, but it’s not necessarily from very many different people.

Lots of companies fight for advertising space on the London Underground. This means the viewer is bombarded with too much information which is not good for getting your message across.

Taxi advertising is “stand alone”, meaning your message is clearer.