I remember reading that the manufacturer stopped producing (or stopped supplying) one of the 3 jabs (I think mumps) for the 3 illnesses covered by the MMR. So some kids had 1-2 jabs but were not able to get the final jab, meaning that they were no fully vaccinated and probably have to get the MMR anyway.
I think there are always risks to vaccinations. I think vaccinations are beneficial to the community because that is how small pox (and tuberculosis) was irradicated. But it is really the parents choice.
Even now with the injections giving at 2,4 and 6 months, it's a combination of 3 vaccines in one needle (DTPa, HIB and I can't remember the other one)