How do you figure out what actually drives car buyers to switch brands?

Surveys alone usually miss the real story — people rationalize their decisions after the fact. I'd pair a quant survey (conjoint analysis works great here to surface true trade-offs like price vs. reliability vs. brand) with 8-10 in-depth interviews focused on the last purchase moment. The interviews are where you catch the emotional triggers and 'final straw' moments that drive switching.