What makes your local stores' one way systems screw up so badly? Every store around here seems to manage perfectly fine. If there are problems with implementation, it's usually with people deciding they can't be bothered to follow the arrows and shop in their normal dithering fashion.
Because people. I know that sometimes its hard to imagine a world where people's lives aren't centred around strict rules and lists, but it is a reality. Take my local Co-op immediately after the lockdown started, they kept to strict numbers in-store (I believe it was little more than a dozen), with staff set aside to "enforce" the one-way system. And so the time it was taking people to shop in-store grew (which will happen if you are forced down isles you where you have no intention of buying anything from), so the queues to get in grew outside. Slowly but surely the counting in, counting out was quietly dropped, and as more people were able to shop at the same time, so staff were required to man checkouts, run stock-ups etc, and thus people just realised that not sticking rigidly to the one way system wasn't going to result in deaths of thousands of people, nor would the Police come crashing through their doors to lock them up. And so as customers relaxed, so did staff, meaning they weren't wheeling stock around the store & back unnecessarily. And do you know what the net result was? Less time in the store per customer. It also means that the shelves are better stocked, and so people aren't having to drive around various stores to get what they need.
Maybe in some places people are sticking to them, that's their choice. But one-way systems are merely part of guidance, there is no compulsion to use them, nor is there evidence that they have any effect. If anything, as above, they seem to actually increase the time people spend in-store, and increase the number of interactions as people wander around isles that they would not otherwise go to. And as I have found in some larger stores that try to use them, they actually cause real problems as queues for checkouts snake up them causing no end of issues.
A very British over-the-top to a solution, that isn't really a solution at all. But if it keeps a few more middle managers locked in endless Skype meetings about the next round of "solutions"....