Having lived in Ireland for a few years, it continually amazes me that mobile phone service provision over here is so abysmal by comparison.
I don't mean in terms of coverage, or cost, or whatever. Just in terms of the policies governing how providers work.
If you've ever tried to port a number from one provider to another in the UK you know that it's a miserable ballache of a process. Operators whinge and moan and insist they can't make it faster/better/easier because of unspecified technical reasons. Yet, across the Irish Sea, operators regularly process such changes within 30 minutes of the request being made.
My suspicion is that, as with many other areas of UK service provision, network providers have gotten used to getting away with a general lack of actual service to the customer, and they resist suggestions like this because they suspect they'll get away with it (because the Regulator has limited powers and seems terrified of using them).
Never mind a "friendly reminder" when you're close to your limit - ask yourself why have they never implemented a system that would cut off your data access when you hit your limit (or some agreed point a bit over it eg 5% above your cap) and redirect you to a page telling you what it'll cost to buy more data access that month? They don't do this because they know people spend more when they're not aware what their usage costs them. It's the same reason that if you're on a £35/month contract but only using a fraction of your minutes/texts/data, they go out of their way *not* to tell you - unless the contract runs out and you threaten to leave.
Across all the providers operating here, the term service applies only in the loosest, most generous sense. I've no objection to them making a profit, but do so in an honest and upfront way, not by being lying gits who hide behind unnecessary bureaucracy.