FAQ About Google PageSpeed Lab Data
Lab data is a Google PageSpeed feature that makes sense of data provided by a predefined set of networks, devices etc.
Lab Data is the system with metrics that measure the performance of the website by taking the data. This system simplifies data science and speeds up experiments.
The largest contentful paint measures when the largest content elements such as the largest image, the text blocks become visible. So if you have an image that is very large in size, you’ll get a very poor result on this metric.