The all-new 2014 Cadillac CTS is a winner, critics say. Can Cadillac tempt BMW loyalists to switch brands? Photo credit: General Motors

It's a truism in the auto business that if you build top-notch products, you'll succeed -- eventually. 

But "eventually" can be a long time, as General Motors (NYSE:GM) is finding out.

General Motors has put a massive effort into making Cadillac's products as good as -- or even better than -- the best from the German luxury brands. That effort is starting to show results: The latest Cadillacs, like the new 2014 CTS sedan, are getting rave reviews from critics, many of whom have dissed GM's products for years.

But Cadillac's sales still aren't what GM would like, as many longtime BMW (NASDAQOTH:BAMXF) and Mercedes-Benz loyalists aren't showing interest. The problem: Cadillac's products have improved, but its image still needs work.

What to do? In this video, contributor John Rosevear looks at the next big challenge facing GM's old luxury brand -- and at how the giant automaker is likely to respond.

Fool contributor John Rosevear owns shares of General Motors. You can connect with him on Twitter at @jrosevearThe Motley Fool recommends BMW and General Motors. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.