Is threatening your customers ever a good idea?

Today, in my inbox, I had an email from an online bookseller with this subject line:

“Last day for FREE shipping in time for Christmas.”

I also had an email from an online drugstore, with this subject line:

“NOW OR NEVER: get $5 dollars off your order and free shipping.”

Although both emails have virtually the same message, the former is URGENT, the latter is THREATENING.

Threatening is telling me that unless I do something there will be consequences (in the drugstore’s case, no more free shipping or something). Urgent is telling me that I should act now because time is running out.

It is more effective to show your customers why they should act now instead of telling them that if they fail to act, they will suffer consequences. Don’t you agree?