this is about as simple as it can get ...

reorg wins over reindex for concurrency. reorg locks only 1-2 pages or 1-2 extents at a time as it executes as opposed to a reindex locking the entire index/table.

reindex wins over reorg in simplicity since it recreates statistics as a result of the reindex process.

so remember always to execute update statistics with a full scan after a reorg.