Others say the region's growth beyond the subway is not Metro's fault. Unlike other systems, Metro must deal with what amounts to three state governments with often varied interests. Additionally, localities control the land near Metro stations and, with a couple of exceptions, have only recently encouraged development next to stations.
"This region probably has the most complex governance structure anywhere in the country, or world," said Robert Puentes, a senior research manager at the Brookings Institution who has studied Metro. "Metro doesn't have any say in how the land is used, and unless jurisdictions plan differently, Metro is always going to be playing catch-up."
Economic experts added that transportation plays a very limited role in county and corporate decision-making. For counties, the primary goal is to build a business base; locating it next to a bus or rail station is a bonus. For companies, the primary goal is to keep costs manageable, which often means looking for cheaper land in less developed spots.
"There is no incentive at all within local governments to distribute the load fairly around the region so the transportation system, let alone Metro, is better utilized," said Stephen S. Fuller, a professor of public policy at George Mason University. Fuller added that, for the typical company, "the transportation services its workforce uses is the least important factor it uses" in determining where to locate.
One example of the way the region has grown was what happened after WorldCom took over MCI. The bulk of MCI employees worked in the company's Washington headquarters and an office in Pentagon City, both within short walks of Metro stations. They eventually were shifted to WorldCom's campus in Loudoun County, more than 15 miles from the nearest subway stop and nowhere near a bus line.
WorldCom officials said the decision made sense for them because they wanted to consolidate operations. Loudoun officials said they welcomed the move because they were desperate to grow their business base. But its effect on regional transportation was that employees who enjoyed Metro access were forced to join the throngs on the highways.
"They took employees who were able to reach their jobs via a variety of means -- driving, carpooling, using Metro and even walking and biking -- and put them in a place where there's no choice but to drive for every trip," said Stewart Schwartz, executive director of the Coalition for Smarter Growth.
Loudoun has since started running a commuter bus from the West Falls Church Metro station to MCI and other firms.
Then there's the issue of personal choice. Many people say Metro is just too expensive, too crowded, too limited to get them to give up their cars.
Michael Zajkowski said there's no easy way for him to get from Oakton to Georgetown each day. If he drives, it takes 45 to 90 minutes. If he goes by Metro, he has to park at Vienna and take a bus from Rosslyn or Foggy Bottom to his office, and the trip still can take 90 minutes.
Zajkowski said the hassle of waiting for a bus and for multiple trains to pass before he can squeeze on keeps him driving. "Metro is full and packed and unpleasant," he said. Metro "cars are not as clean as they used to be, and they smell sometimes. It's a long ride home."
Willa Woodson said she's not even sure how she would get from her Rockville home to her Gaithersburg job by Metro. "I'm sure there is" a way, Woodson said, "but I've never looked into it. I just prefer to drive. I'm spoiled."
Nonetheless, Metro ridership is on the rise. On a typical day, people take about 650,000 trips on the subway, and 10 of Metro's 13 busiest days were within the past nine months.
Transit officials and regional leaders said they are seeing a slow shift in attitudes that could increase Metro's popularity. The District and inner counties are focusing development at subway stations, and outer counties have restricted some development until a Metro line is built.
At the same time, the system is being augmented by such things as a circular bus line in downtown Washington and a light-rail line in Anacostia. Metro is also on the move, as officials pursue an extension through Tysons Corner to Dulles Airport and eastern Loudoun County.
Planners said it's not unusual for a subway system to start as Washington's has. Some cities, like New York, London and Paris, go on to build immense subways. Others are satisfied with a few commuter lines.
The question that faces Washingtonians is, in a world of limited money, whether they're satisfied with a collection of lines that primarily serve commuters coming to the region's traditional core or whether they and the federal government want to spend billions to construct an encompassing system that covers the region.
"We would be crazy to stop," said Dan Tangherlini, the District's transportation director and a newly appointed Metro board member. "We have to figure out ways to get people around and connect them to where they want to be."