The other side is not giving you adequate discovery responses. In frustration, you may want to file a motion to compel. But stay calm and consider carefully whether doing so really makes sense and if there are better alternatives.
Updated 8/17/15: Companies are increasingly turning to automated hold processes to make a legal hold smoother and more legally defensible.
When the duty to preserve electronic evidence arises and how far it extends can be the subject of heated dispute. One thing is clear, however: When the duty to preserve evidence is triggered by pending litigation or the possibility of future litigation, don’t hit that delete button!