It's probably one of the reasons why the BBC News website is popular. All articles were originally written so that the first three or four paragraphs could be cut off, and presented as full articles on teletext (a tv text service), so the whole story had to be summarized within that space. They still write their articles in that way, even though teletext is increasingly un-used.

I should say, though, that it does mean that the content of that summary, and of the headline, becomes extremely important. For instance, you could nominally cover a news story, but write a boring headline and summary, and very few people will trudge through that to find the really important details later on. You do sometimes find that occurring on the BBC site, especially when it's a story which might raise a lot of controversy within government.