When Chinese electric vehicle maker BYD opened its first Southeast Asian factory in Thailand earlier this month, the nation of 66 million people basked in the limelight and won praise for its industrial vision.

What, however, received less attention was an announcement by another big automobile manufacturer — Suzuki Motor — just a few weeks earlier that it will shutter a Thai factory that produced as many as 60,000 cars a year.

The Japanese automaker's move mirrors those by scores of other companies in Southeast Asia's second-biggest economy, which is bearing the brunt of cheap imports from China and a slide in industrial competitiveness due to factors including rising energy prices and an aging workforce.