Anything to the effect of “this ring isn’t expensive enough” is the only reason you need to never marry that person.
My (former) best friend got married young, and her and her husband had rings they got at the flea market that cost about 20 bucks a piece. I always respected the hell out of her for that. Her sisters tried to make it out like it was some kind of bad omen, or like it meant they didn’t love each other. She had a lot of pressure to cave into and act like a snotty brat about the cost of the rings. She never did, and loved her cheap ass flea market ring.
She turned out to be a terrible person in a multitude of other ways, but on that note, good for her.