It's not you.
I've had some odd interviews over the years. One in which the head of IT was a Luddite - and proud of it. One in which the phone and HR interviews went well, but the interview with the manager left me wondering if she had psychological problems
And, of course, sometimes the interview is for show. They've got someone they want, but have to keep HR happy, and demonstrate they considered other candidates.
My best advice is a) research the company/position, b) be honest, and c) try and be positive. Note that 'being honest' doesn't preclude omitting horrendous things. e.g. "I made an internal transfer as soon as I realized my boss was a lying, backstabbing hypocritical s.o.b., and was much happier with my new position." can be reworded as "I made an internal transfer, after achieving some great things in my first position, because the new job offered more opportunities for professional development."