Or that they didn't have a good lawyer.
Honestly, as long as we agree they actually had damages, I doubt this would be an obvious conclusion. For example, they might have realized along the way (or early on) that the case was going in a direction where there wasn't much of a point in investing a lot of money into it. Or they changed their mind because at some point (after they filed) lots of people said suing a TV show like Top Gear/BBC is not a good idea as they will easily find ways to make it not worth your effort. Or that they had the impression the "it's just a comedy" argument was gaining ground in public (even though not correct, as we discussed here).