Not really if you think about it. Once you find what you consider a good stock (investment) then timing , luck , and patience come into play. The only way a company can let you down is in not doing or achieving the goals they set up for the company. There is often market nonsense that has to be recognized for what it is or that too can have a play.
It is not always ENOUGH to "KNOW WHAT YOU OWN" helps to have a feel for what other players are doing.