The 19-year-old left-arm wrist-spinner was impressive after picking up eight wickets in five games at an average of 28.50, and also showed good variations across the series.
Reflecting on Lawes' selection and performance, Sammy praised the teenager despite a 3-2 series defeat against the Black Caps.
"I would say I'm proud of what he's done," Sammy said. "Taking a chance on a kid who's never played (even) a game, in a region where you're not sure how fast a player will develop. And we didn't pick Lawes just out of our heart.
"The processes that we followed in fast-tracking his development, a lot of people don't see that. I heard a lot of noise when he was selected, but we, and guys like Nikita Miller, who put in the work, and Lawes himself, credit must go to him.
"But the processes we followed to get him to where we believed he was ready to play international cricket, we were quite happy with it. And we have a couple of (other) youngsters who we put in through that process as well.
"And Lawes, after the series, I said, you know, I'm really proud of him to come out [with] eight wickets, looking like he belongs in the game and especially (with) us trying to develop players. Really proud of what he's done in his debut series."
West Indies' next assignment is a two-match Test series against Pakistan, which is set to begin in Tarouba on Saturday.
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