This means that render template uses the video quality setting, which is specified in the Project Properties.
You can explicitly set it to Best (or Good) to override it. The difference between Good and Best is described in the help:
“Unless you have specific performance problems, choose Good. Choosing Best can dramatically increase rendering times. Good uses bilinear scaling without integration, while Best uses bicubic scaling with integration. If you’re using high-resolution stills (or video) that will be scaled down to the final output size, choosing Best can prevent artifacts.”
Vegasaur – automation plugins and tools for Sony Vegas Pro