The offices of the Asan car suppliers' union resemble a bygone era. Walls are decorated with fading photographs of past protests. Cigarette smoke wafts from the foyer, where workers in overalls lounge on battered sofas enjoying a break between shifts. Most are well into middle age.

Do Sung-Dae, the union's boss — shock of gray hair, horn-rimmed glasses, waistcoat heavy with pins supporting various causes — is locked in a struggle with Yoosung Enterprise, a parts maker that employs its members in Asan, an industrial city south of the capital, Seoul.

Korean parts-producers are being squeezed. More have filed for bankruptcy protection since last autumn than at any time since the financial crisis in 2008. Plenty, including Yoosung, claim they are fighting for survival. Their troubles are a symptom of a deepening crisis in the industry. At the industry's center is a single giant firm: Hyundai Motor Co.

In 20 years Hyundai Motor — which also controls Kia — went from being barely known to the world's fifth-biggest carmaker by churning out decent if unexciting cars that were cheaper than similar ones produced by Japanese or Western competitors. Like Asan's union offices, however, it has failed to keep up with the times.

Hyundai's global sales were stagnant at $85 billion last year. Net profit declined in 2018 for the sixth year in a row.

Since 2014, its shares have underperformed major peers such as Toyota, General Motors and Ford, measured in dollars. Some reasons for this lie beyond Hyundai's control. A weak yen boosted Japanese producers. The trade dispute between the United States and China, as well as separate threats by President Donald Trump to impose additional tariffs on Korean cars, did not help. Its business in China was hit by a yearlong Chinese boycott of South Korean products that followed a dispute over South Korea's new missile-defense system in 2017.

Many problems, though, are homegrown. Hyundai's move upmarket in the past few years exposed it to fiercer competition. It missed the shift toward SUVs in Europe, the U.S. and, most recently, China. Its Genesis brand has lagged behind in the highest-margin premium segment.

Half of its production capacity in China now sits idle — aggressive expansion may have more to do with this than the boycott, said James Lim of Dalton Investments, an asset manager.

Rising labor costs at home, where it produces 40 percent of output, have crimped Hyundai's ability to compete on price. "Customers still expect our cars to be cheaper than, say, a Volkswagen," said Cho Won-hong, the firm's chief strategist.

Cho wants to persuade them to pay more, by betting on future technologies such as hydrogen fuel cells and loosely defined "integrated mobility" (car-sharing, autonomous vehicles and the like).

Yet Hyundai channels 3 percent of sales to research and development, compared with 6 percent at Volkswagen or Toyota's 4 percent, according to Bloomberg.

Some analysts blame the R&D shortfall on high labor costs. Others point to the old habits of the chaebol, the South Korean conglomerates of which Hyundai's parent company is one of the biggest. In good times it plowed spare cash from its carmaking arm on speculative property investments in Seoul's glitzy Gangnam district and bought back a struggling construction company.