https://www.cnet.com/news/pixel-3-xl-rumors-russian-leak-google-launch-specs-release-date-price-leaks-android-pie-notch/

Google will also want to avoid the mistakes associated with its previous Pixel 2 XL. That phone suffered from burn-in issues and other defects related to the phone's OLED display -- missteps which resulted in quite a bit of media attention, marring some initial positive reviews with caveats. It also brought the spotlight to Google's warranty, which was eventually broadened to accommodate the issues. (Note that the iPhone X's OLED display is not immune from burn-in either.) 

Again, the company hasn't formally announced the Pixel 3 phones, so most of what we think we know is based on rumor and hearsay. However, because the Pixel 2 and the Pixel 2 XL and are among the best phones on the market today on account of their excellent cameras, snappy performance and tight integration with Google's homegrown Android software, many are interested in what Google will offer this time around.