In early June, Netflix content chief Ted Sarandos met with several dozen of his middle-ranking and senior film and TV executives and delivered a blunt message: Be more careful with money.

Mr. Sarandos told the group that spending on film and TV projects, particularly big budget movies, needed to be more cost-effective, according to people familiar with the meeting. Netflix has long measured the efficiency of its TV shows and movies using a ratio of their cost to a measure of viewership that gives more weight to new subscribers and those viewed at risk of canceling, say former employees. Mr. Sarandos made clear that in the future big-budget projects should bring in lots of viewers, a shift from the past when they might have gotten a pass if they were expected to get buzz and build industry credibility.