Even the biggest and best companies can be hit by the capriciousness of the High Street. For example the run-flat tyre which, after the worst puncture, will still carry you safely at 60 mph for a further 100 miles. But can the tyre makers persuade the car men to adapt their designs to take the new wheel? The answer lies, partly at least, with the customer. Again, the drink-in-a-tube is a brave attempt by a major plastics company to break into the enormous fizzy drinks market. But that scene is already hotly contested by the makers of bottles and cans. The result is a fierce three-way battle for the thirsty customer. The Risk Business this week discovers that some very unfunny things can happen on the way to market.