AI: why did Harold Wilson's attempt to control shopping prices fail so badly?

LEARN FROM PREVIOUS LABOUR FAILURES, Mr Burnham. Your 'New Plan' Isn't New AND It Doesn't Work!                                         

Harold Wilson’s attempts to control prices—pursued through the National Board for Prices and Incomes and statutory freezes—failed because they clashed with powerful trade unions, worsened underlying inflation, and lacked enforcement mechanisms that could withstand global economic pressures. [1, 2, 3]

Core Causes of Failure

Union Resistance: Trade unions fiercely rejected wage restraints that accompanied price freezes, rendering voluntary compliance unworkable. [1]
External Pressures: Devaluation of the pound in 1967 made imported goods significantly more expensive, undercutting any domestic attempt to keep shopping costs low. [1, 2]
Distorted Markets: Direct state interference failed to address root structural deficits in British industrial productivity, treating symptoms rather than causes. [1, 2]