There are at least two things that spring to my mind: The United Kingdom has not been nor is yet blessed with the ability to deal well with things, even when what works elsewhere which just needs to be copied is readily available - belatedly taken up more recently, and it worked. In tackling the present case the country has always had the huge advantage of being an island but wasted it for 10 months or more. Managing the inevitable leaks coming in should have been maybe not a walk in the park but certainly attainable.
The other is that people (in the UK) seem to see the running of the country as a dictatorship, his eminence Boris being the dictator - is that really so ? Again a comparison with others: The politicians are nowhere to be seen, the competent authorities propose, design and implement a public guidance/education programme together with setting rules for restrictions in public life - and the public enthusiastically complies (there). The government approves the recommendations of the competent people with an analogous involvement to that of the queen signing UK legislature. This works and the countries concerned, certainly not the politicians, never refer to themselves as the World's Best, etc. The UK could have copied but the World's best need by definition to do things in their unique way - can you hear the 130,000 dead clapping on their doorsteps ?