There are two types of ministerial regret.
There’s the grand, heroic version – where a signature policy or life-shaping idea failed to survive on hitting reality. Kwarteng’s economic plans, for instance.
And there’s the quieter, sin-of-omission style regret. The unintended consequences of ill-considered plans.
In his 2017 book A Higher Education David Willetts notes:
One of my great regrets looking back on my time as universities minister is that the number of part-time students fell so sharply. We thought we were offering them more help by, for the first time, extending loans to them to cover their fees.
Funnily enough, he seemed less concerned at the time.