Boris is an incompetent ineffective gambler. Every gambler gets one right eventually and his government took a huge gamble when they bought on spec a shitload of vaccines, prior to the completion of their trials. I am pleased that he finally, and apparently, got one right. Although it's taken nearly a year since all those Cobra meetings about Covid early last year which he was just too too busy to attend.
I write, apparently got one right, because although the UK is ahead of the curve on vaccination, the efficacy of the methods being used has yet to be demonstrated and everyone being vaccinated is effectively taking part in the Phase Four trials.