Why do some big successful brands go bust?

Toast is back for a new series, taking a look at the decisions that often left investors burnt.

I'm Sean Farrington, a BBC business journalist. I'll be hearing about the hype.

They're going to do the deal that makes them the most money at that point of time.

And I'm picking what went wrong, talking to owners and employees to ask, what can we learn?

It was being undercut by similar rivals. It just couldn't survive.

Toast. Listen first on BBC Sounds.

Hello and welcome to more or less on the BBC World Service, the programme which sifts through

the haystack of numerical news looking for the needle of accuracy. I'm Tim Harford.

Last week, while schools and businesses across Europe closed in an attempt to halt the spread

of coronavirus, the UK stood alone in a more relaxed approach to the approaching

pandemic, letting people choose whether they wanted to go to work or socially distance themselves.

And this week, well, this week I'm speaking to you from under a duvet in my bedroom while the

schools prepare to close for the foreseeable future. The British government says

their change of heart was based on the work of scientists like our guest. My name is Crystal

Donnelly. I'm a professor at both Imperial College in the School of Public Health and also at

University of Oxford in the Department of Statistics. So what has Crystal found that caused such concern?

She started back in January, analyzing the number of cases of COVID-19 diagnosed in different

countries.

We were able to estimate what's called the basic reproduction number.

Now, that's key to studying infectious diseases because that's the average

number of people, one infected person caused in a fully susceptible population. Combining that

...