Why DAL do it:
They add depth without giving up picks
Richards is a very good lob threat and interior presence
Martin can add them energy and defense off the bench while they can hope Martin find his efficiency back within a better offense
Adding a second is valuable to use the second-round exception as they control their finances
Why CHA do it:
Holmes get them a big body to still have a center to play while Williams is injured
OMax can potentially be a defensive minded forward for their future