If it ain't broke, don't spin it out.

First Netflix decided against hiving off its DVD-by-mail business, and now Hewlett-Packard says it won't offload its PC unit. Kudos to new Chief Executive Meg Whitman for a quick decision, though it could yet prove to be the wrong one if the PC market deteriorates further.

Ex-CEO Leo Apotheker perplexed shareholders and, more importantly, customers when in August he said H-P was exploring options for its PC unit. While suggesting a spinoff was likely, he added to the uncertainty when he said that H-P might, in fact, do nothing. Ever since that confusing announcement, H-P has faced questions about what it wants to be.

Ultimately, H-P decided the cost of dumping the business was just too high. For starters, H-P saves money procuring server parts, thanks to its scale in the PC business. Also, it would have proved very expensive to build a new brand and new corporate structure for the spun-out unit, not to mention the lost opportunity to increase sales by bundling lots of hardware together for customers.

Yet if H-P ever was going to escape the low-margin PC business, now would seem to have been an opportune moment. H-P's market share is still tops, with 18% of global PC shipments by volume in the third quarter, according to IDC. Yet its share is actually down a bit from two years ago, as Asian rivals Lenovo and ASUS have grown quickly.

At about 6%, H-P may have achieved peak operating-profit margins for the business. And growth for PCs has been sluggish, thanks in part to the popularity of mobile devices like Apple's iPad.

Ms. Whitman has decided H-P will remain a behemoth hardware company, for better or worse.