As we well know, players can look spectacular in Summer League and flop upon the arrival at training camp - very similar to summer romances.
It comes down to determining if what an analyst sees in the summer can translate to worthiness for a standard NBA contract. We saw Jayson Tatum prior to his rookie season play at a high level in 2017 Summer League, and he parlayed that performance into a stellar rookie season, including a playoff run all the way to the Eastern Finals.
Summer League-2018 ended recently for the Celtics, and there were some promising signs for the upcoming season.