 It has been rumored for years that Harrison Ford (I) (qv)  purposefully gave a bad reading of the voiceover narration added  during post production in hopes that the studio wouldnt use it.  Ford has denied this vehemently, stating that he gave the voice over  six different readings and neither version came out sounding right  and that the narration didnt work simply because the film wasnt  originally made to have one.