Does a bad review ruin a films chances?

Traditionally, film reviews have been seen as a way to assess the artistic merit and public appeal of a movie. Filmgoers use reviews to help them determine whether to view a particular film. As the number of film fans following the advice of reviewers grew, film companies saw profits diminish across a broader number of films. In order to counter this development, film studios increased marketing budgets and avenues of marketing to create more interest in a movie prior to the opening.
In recent times, the impact reviews have on a film's box office performance and DVD rentals/sales have become a matter for debate. There are those who think modern movie marketing, using pop culture convention appearances and social media along with traditional means of advertising, have become so invasive and well financed that established reviewers with legitimate criticism cannot be heard over the din of popular support. Moreover, this has led, in part, to a decline in the readership of many reviewers for newspapers and other print publications. The vast majority of film critics on television and radio have all but disappeared over the last thirty years, as well. It can be observed that most of the discussion of film on television is focused on the amount of box office business a film does, as if financial success were the only criterion needed to define artistic success. Today arts criticism in general does not hold the same place it once held with the general public.
Conversely, it's been claimed positive film reviews have been known to spark interest in little-known films. For example, independent films with smaller marketing budgets, such as The Hurt Locker, are promoted more widely thanks to the positive reviews they received
I know personally for myself that if someone tells me a film is bad, I still want to make my own judgement and not just rely on someone else's opinion. Obviously there are still going to be people who read a review and then refuse to pay cinema prices to see it, but often they will eventually see the film by watching it with a friend on dvd. Some films can receive really bad reviews but still break box office charts merely by the name behind them. For example 'The Hangover Part 2' receieved relatively low ratings on film sites such as 'Rotten Tomatoes' but still managed to become the highest-grossing worldwide opening of a comedy film. This is mainly due to the franchise of The Hangover and people enjoying the first one so much that they wanted to watch the sequel even if it wasn't as good as the first.