Supplying systems may not be path to profits.

In the last 10 years, automakers have responded to the fiercer pace of competition in many ways. They have targeted new markets and niches. They have focused on building brands. And they have outsourced.

Automakers' decision to purchase parts rather than build them has brought the biggest changes for suppliers. Many have responded by supplying a group of parts, or systems, instead of single parts.

But the promises of that strategy have not always been delivered. Before following it any further, suppliers should ask some vital questions.

Do they have what it takes to be big? Or ...