How do I turn down the possibility of a relationship?

i met this guy over hinge and he turned out to be the sweetest, most thoughtful guy i’ve ever met. we’ve been on 3 dates and we’ve made out once. at first i thought i could see myself liking and falling for him but as i slowly got to know him, my feelings for him were falling out. work ethic and having a drive in life is very important for me when it comes to finding a partner and these two qualities are what this guy lacks. im thinking of talking to him in person to give him closure but im having such a hard time thinking about how to open up this conversation about why im ending this “seeing” phase in a polite manner. i want to say that i have such big ambitions and motivation in life that he clearly doesn’t have. what can i say?
How do I turn down the possibility of a relationship?
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