Rather: they are very helpful at finding errors early on and can nearly eliminate some classes of error.
Rather: they work largely by making you think very hard about the system you propose to build.
Rather: they are useful for almost any application.
Rather: they are based on mathematical specifications, which are much easier to understand than programs.
Rather: they can decrease the cost.
Rather: they help clients understand what they are buying.
Rather: they are being used successfully on practical projects in industry.Quoted from: J. Anthony Hall, Seven myths of formal methods, IEEE Software, 7(5):11-19, September 1990.