Why Does "Taking Things Slow" Often Feel Like a Polite Brush-Off?

I’ve noticed a pattern where “let’s take things slow” seems less about pacing and more about keeping options open. It’s frustrating when what sounds like consideration ends up feeling like disinterest. Has anyone else experienced this? How do you tell the difference between genuine caution and someone just stringing you along? Would love to hear your thoughts especially if you’ve navigated this in dating or even professional relationships.