One advantage of building the telephone into your sales or marketing is that you can often test very small numbers to determine if the message is right or needs some adaptation because results are immediate.

Testing has been implemented in both and outbound and an inbound scenario, depending on the objective that needs to be met and the integration of sales and marketing.

You are testing the market, the approach, the associate, the offer. The same amount of your commitments should be put into the test; in fact I'd venture to say more of a commitment.

You should be continually testing, learning and building on that knowledge. Again, the information you learn during that call can allow you to turn a campaign right around to improve results.
Create an environment that encourages sharing of information, because real phone communication brings incredible information.