"Two years from now, spam will be solved." - Bill Gates, 2004
Well, that didn't happen.
I don't know about you but I will block anyone on social who sends me a direct message immediately after I follow them. Many times their intent is not relevant or is of a very non-professional nature and unrelated to their business.
Direct messages are trendy, especially now that you can easily automate them, yet they have become unoriginal and spammy. The reaction of your audience is what builds your reputation. People love connections and relationships flourish when associating with brands on a personal level. If your company habitually populates the same canned message, you will forfeit potential customers to the business across town, and you will have a lower click-through rate on your direct messages.
If your business model and strategy includes employing direct messages, make sure that they provide relevant information. For example, if you are a fitness trainer, you could have an automated message with a link to a recipe or mini-workout.
Think of it this way, be a problem solver for your potential customer, not the problem.