I sometimes think those acronyms are the emotional safety labels for romance reading. HEA means the couple rides into a sunset we actually see, vows exchanged, kids maybe hinted at, the whole classic package. HFN feels more honest for a lot of modern settings—they've overcome the big internal conflict, they're committed, but the future's still a bit open. It tells me the author's priority is the emotional payoff of the relationship stabilizing, not necessarily the final page of an epilogue fifty years later. The indication is about the reader's need for certainty versus hope.
For books with darker themes or high-stakes plots, that HEA tag is a lifeline. It's a promise that after all the psychological torment or external danger, the narrative will honor the couple's bond with permanence. Without it, I'd be too anxious to enjoy the journey. Conversely, a HFN in a contemporary or new adult novel often suits me better; it suggests a maturity, acknowledging that 'ever after' is a choice they're making now, not a fairy-tale guarantee. It shifts the focus from a destination to a solid, believable new beginning.