Trading the number one pick before the draft is probably preferable to trading it after the selection has been made. Before the draft, teams could be interested in selecting any number of different players, whether it's Nerlens Noel, Victor Oladipo, or Ben McLemore, the Cavaliers can work with team's regardless of who they are interested in.
After the selection has been made, however, the flexibility weakens somewhat. If the Cavaliers select Ben McLemore, the Cavs will only be able to trade with teams that either need a shooting guard or have fallen in love with McLemore. Teams interested in Nerlens Noel would be trying to make trades with Orlando, in all likelihood. Of course, the Cavaliers could decide to keep the pick and take Nerlens Noel and keep him. That would be cool.
Chad Ford, though, indicates that the Cavaliers aren't going to stop trying to move their pick, even after the selection has been announced.
What I know this morning: 1. Cavs 1st option is to trade the pick. Looking for a young veteran + a 2014 lottery pick in return— Chad Ford (@chadfordinsider) June 27, 2013
What I know this morning: 2. If the Cavs use the No. 1 pick, don't assume they keep it. Will continue to shop it after the draft.— Chad Ford (@chadfordinsider) June 27, 2013
What I know this morning: 3. Hardest asset to get rt now is a '14 lottery pick. Odds at 95% that NO team gives up one. 14 Draft too strong— Chad Ford (@chadfordinsider) June 27, 2013
What can we take from this? The Cavaliers want assets that other teams are not likely to want to give up. This means that the Cavaliers should probably take the guy they want the most and if they can pull off a trade, good for them. They could decide to take the guy who would be most appealing to other teams in the hope that they can pull off a trade, regardless of fit or how they see the player. This might make Ben McLemore or Victor Oladipo more appealing to Grant if he believes he is more likely to get better assets back for those guys.
I worry that as we get closer to the draft that Grant really doesn't like these players much, and ends up taking a deal for the number one pick that doesn't bring back enough value. But we really don't know anything at all.