Why is the ability to lock the front wheels of my Joolz Geo an advantage?

The front wheels can be locked by means of the grey buttons. By pushing the buttons down the front swivel wheels are locked and stop swivelling. Locking the front swivel wheels is particularly an advantage when walking on a bumpy road. By locking the front wheels you walk in a straight line and you prevent the front wheels from finding their own path and change course.