Held for a long enough period a stock will ultimately give a return which will be close to the return on capital given by the underlying business it represents regardless of the price you purchased it at. If you purchased it at a high price you may have to wait for several years before it shows a return but ultimately returns will closely track the underlying return on capital if you hang on to it till judgement day.
The key question is how long are you willing to hold on to a stock that shows great ROC but prices move up and down living a life that seems to be independent of the business they are supposed to represent. Since for a large percentage of businesses no one can predict how long a particular ROC can sustain itself the return can also not be predicted.
Thats why financially stable businesses with little change in consumer behavior command a high multiple as the ROC is locked in for a long period of time.