There's nothing really to see here, other than the fact that there's no real point in trading anyone for a likely late 2nd-rounder. They're probably just doing right by Calathes, and freeing themselves from a contract they were going to have to deal with eventually.
Then again, it's hard to give the Mavs the benefit of the doubt when it comes to choices like Calathes vs. Mekel, which is what this came down to. Calathes was the MVP of the Eurocup, a hugely prestigious tournament that is highly regarded. Mekel was the MVP of the not-too highly regarded Israeli league. Mekel could still be better than Calathes and, whether or not he is, the Mavs could certainly feel that what Mekel might be would be a better stylistic fit for what they want to do.
It's just that the Mavs are so often prone to the unexpected, to the low percentage play, and it hasn't tended to pan out for them. It's Cuban's unquenchable optimism that makes something like Zeller for Crowder, James and Cunninham sound like a coup, for example, and we wouldn't have it any way. But sometimes you could wish that the Mavs would just draft whoever Chad Ford, or our own Jonathan Tjarks, thinks they should and you could wish they'd take the Eurocup MVP over the Israeli League MVP.
But they didn't! And for all anyone could possibly know they were 100% right to do so. Likely to be a low-impact move, either way. Bring on Gal Mekel.