Yes, there are warnings against trusting defensive metrics as reliable until three full seasons of data is collected. However, I will still compare UZR/150 with small and unequal numbers of innings, because at least it's something. Take it or leave it! For example, should we start Danny Santana at shortstop full time throughout 2017 and 2018 to decide if he should be our starting shortstop in 2019? After all, we only have that one season of data on him.