By nearly all measures, Google has the most successful online advertising platform in the world. But while the search giant is often lauded for its algorithms, the truth is that products like AdWords are always a work in progress, and much of that progress is made by humans who monitor the system on an hourly basis.

The New York Times recently ran a feature that profiles Nicholas Fox's "ad quality" team inside of Google. The team, which charts an endless stream of data, works to constantly refine Google's ad auction system based on what it's learned.

One big change Fox and his team have made over the years is to factor its Quality Score rank into the bidding process. That means that advertisers directing traffic to higher quality pages may be able to obtain better placement than competitors who are willing to pay more but offer less.

Though seemingly counterintuitive, the process is meant to favor ads that are more likely to get clicks, which benefits Google but often puts the company at odds with some advertisers. However, Fox said that adjusting the Quality Score gives advertisers an incentive to improve their ads, which benefits users.

Google is also expected to start including page load time into the equation some time in the future because it has found that users often give up on pages that don't load fast enough.

That policy of user-centric rules for advertisers has served Google well. But while the search giant continues to see strong growth in online advertising, some fear that the data streams Fox and his team rely on may draw unwanted criticism from users. However, if there is a backlash, Fox and his team are likely to be among the first to see such a trend. In late February, when many were worried that an economic slowdown could spread to online advertising, all eyes turned to Google, using the company as something of a benchmark for the industry. While Google saw a drop in clicks, Fox and his team were able to determine that the slowdown that was affecting Google was caused by several minor but unrelated events.