The Power of the Word "Because" To Get People To Do Stuff | Psychology Today
Using the word “because” and giving a reason resulted in significantly more compliance. This was true even when the reason was not very compelling (“because I have to make copies"). The researchers hypothesize that people go on “automatic” behavior or “mindlessness” as a form of a heuristic, or short-cut. And hearing the word “because” followed by a reason (no matter how lame the reason is), causes us to comply.
They also repeated the experiment for a request to copy 20 pages rather than five. In that case, only the “because I’m in a rush” reason resulted in compliance.
So what does this all mean?:
When the stakes are low people will engage in automatic behavior. If your request is small then follow the request with the word "because" and give any reason.
If the stakes are high, then there is a little more resistance, but still not too much. Use the word "because" and try to come up with at least a slightly more compelling reason.
