Summary
Martin has some doubters coming into the 2020 draft, as some draft evaluators did not see him as someone that should be drafted. Nevertheless, the Rockets selected him with the 52nd pick, and he looks to be a steal at that spot. Martin didn't really start to see minutes until the Rockets' season was down the drain, so the context of his success is a little tricky, but he appears to have some real upside.

Martin is an athletic wing that can finish well above the rim, and has had some legitimate poster dunks. He also shot an above-average 37% from three, but we'll probably need to see a bigger sample before we can really know if his shooting is legitimate. Martin rebounds well for a wing and also has a really nice block rate. Although Martin's contract is non-guaranteed for '21-'22, it's almost certain that the Rockets keep him around.
 
Cap Considerations
Martin's $1.5 million salary for 2021-2022 is non-guaranteed, and if he is waived he will become an unrestricted free agent and the Rockets will have no form of Bird rights on him. If he is waived, any team could claim him off waivers since he is on a minimum contract.

If Martin becomes a free agent, other teams will have multiple ways to sign him as even teams without cap space could possibly use either of the Non-Taxpayer MLE, Taxpayer MLE, or possibly even the Room MLE to sign him. If Martin is waived and clears waivers, his value will likely be low enough that he would only have offers for the minimum.