Give them the truth!

I've just returned from the local service station. My car needed a new bulb in one of the headlights and Peugeots being what they are, it wasn't something I could easily do myself. I asked the man behind the counter how long it would take, since I have a lot to do today. "Oh, twenty minutes, if that," he assured me airily. Perfect.

Half an hour later, I asked for a progress check on the rather elastic 20 minutes. "Just a few more minutes," a different man told me.

A good 15 minutes or more later, the first man re-appeared to tell me that my car also needed a new wiper blade. I pointed out that I had already been there more than double the original estimate of 20 minutes. He explained that they have to do a health check on every car. "This is fine... and commendable, " I said, "but when a person asks you how long something is going to take, you should factor that in, so that they can plan accordingly." He sighed. "Look, do you want your wiper blade replacing (sic) or not?"

Not. Thanks. That much I can do for myself.

And next time my car needs work, I'll be going somewhere else.

We need to beware of this, too when we're trying desperately to sell someone on an idea/solution/whatever. If we boost their expectations and under-deliver, we will only alienate them even further. Our job is tough enough as it is.