I’m not party to the communications but my understanding is that comparison websites (or at a minimum mse’s cheap energy site) tell switchers “YOUR SWITCH IS IN PROGRESS...”
This is incorrect or at the very least ambiguous because the switch isn’t in progress until the customer completes the verification progress. Whilst I agree that the majority of switchers do complete, some are still “misled” by this and don’t realise that they need take further action to complete.
This need fixing, the best place to fix it would be at the comparison site end, perhaps by annotation of the message from them to say to complete your switch click here (or whatever other solution may be forthcoming.)
If a customer ends up in the community saying what’s happened to my switch then the system has failed that customer.