Here is a clip showing you how one light can make a big difference in your video quality and feel.
First clip is only using ambient light, which sometimes we tend to use when in a time crunch, as you can tell the video looks amateur, its bad in quality and under exposed. Try to avoid at all cost unless room is filled with looks of light.
Second, I'm using the on camera light which most video journalist tend to use more times than not. Now, you have some fill and the subject is lite better than using ambient light but the image looks flat and you will at times run into glare off the glasses.
Third, I used one light to light up my subject and look at the difference. There is some shape to the face of my subject and some contrast between my subject and the background. Try to use at least one light to get your subject justice, use your surroundings to give interesting backgrounds and avoid white walls.
One light can make a difference in the quality and feel of your story