There are two front suspension arms, one at each side.
On the inboard end of each one, are two joints, which allow the arms to pivot up and down, so you get your up/down suspension travel. These joints contain rubber bushes, essential to reduce the amount of vibration transmitted through the car.
However, these arms must not be allowed to move backwards or forwards, otherwise the geometry will change - if they do move backwards or forwards, the attached front wheel will turn one way or the other.
Sometimes the rubber bushes perish or deteriorate, allowing this sort of movement.
Mk4 Ibizas, well the earlier ones anyway, had rubber bushes which commonly failed because they were made with large voids in, allowing lots of movement and rubbish handling...
The Cupra had solid rubber bushes which was a big improvement - I can't remember whether Seat started fitting them to all Mk4 or just the Cupras.