Travelling on the M 25

On my way with my dad, to the Royal National Orthopaedic Hospital, in Stanmore, travelling on the M25 northbound. The car in front of us was all over the place in the outside lane. It got got very close to clipping the lorry next to it a couple of times.
When we pull off to a slip lane, we came alone the same car. Thats when we noticed that the driver of the could barely see over the steering wheel.
Thank goodness we didn't travel all the way behind it. It would have been a really scarey journey.