*UPDATE Uber has changed their rating policy so you can no longer change a driver rating after you submit. This is from Uber's website: "Please take time to consider the most appropriate rating for the driver's behavior during the trip. We do not change driver ratings once they have been entered into the app."
As you may know, one of the most important aspects of rideshare services is the rider and driver feedback. This feedback is mainly given through a star-rating system where both riders and drivers can rate their experience out of 5-stars, and this feedback determines your overall "score" on the app. Although it may seem menial, ratings mean a lot for rideshare drivers.
Have you ever driven in an Uber or Lyft and accidentally given the driver a bad rating? This bad rating may impact the driver, and there is indeed a way for you to alter the rating so it may not have a negative impact.
For Uber, you can update your rating for a driver by opening the receipt from your Uber trip. The receipt is always sent to you via email from Uber, and it contains the details of where you traveled, how much it cost, and the driver rating. Through this receipt you can select the number of stars you want to rate your driver, and it will automatically update the rating given you provide confirmation of the change.
Using the Uber app, you can also view the previous ratings you have given drivers under the "Trips" tab in the main menu of the Uber app.
Update: You can also contact Uber using these links.
Like Uber, after your Lyft ride both passengers and drivers are prompted to give a rating of their overall trip experience out of 5-stars. The process for changing your rating of a driver or rider is different from Uber. For a Lyft ride, you cannot change the rating through the app, instead you have to send Lyft a message that includes information about the passenger/driver name, the time and date of your trip, and what you would like to change your rating to and why.