Zero-hour is an arbitrary limit
Labour are only going to ban exploitative zero-hour contracts. They want you to think that means that all zero-hour contracts are exploitative, so they'll be banned. Of course, what it actually means is that they'll only ban the ones they have deemed to be exploitative - which certainly won't include any connected to a Labour politician, or donor for that matter.
If I'm honest I'd much rather we focussed on the exploitative bit, rather than an arbitrary number of hours. If a zero-hour contract is exploitative, surely a one-hour contract is almost as exploitative? I was on one during my student days, and although the flexibility suited me well, I can see how it could easily have been abused by a less-scrupulous employer, especially if had been a job whose income I needed, rather than like to have.
Rather than some vague aspirational soundbite, how about some concrete measures? I'd think if we had protection against detriment from refusing overtime, and the requirement that sick and holiday pay be based on the average hours actually worked over some period (perhaps the 17 weeks employers should already be monitoring for the 48-hour week) then we could keep zero hour contracts and the "flexibility" that business claims is so important, while also improving the lot of employees on all contracts, not just zero-hour ones.