Well, isn't it fairly common for veterans to hang around for the first half of the season, gauge the interest from teams, and then get signed to a contender around the All-Star break? Plus teams want to see what they have with their own situations before signing another man. PJ Brown being signed by the Celtics is a good example of that. Collins isn't the type of player that Brown is, but the situation is similar. Just because the Clippers could have signed him to a contract earlier in theory, it doesn't mean they could have actually signed him or will willing to sign him.