One thing that may appeal to readers of Robert Frost's "The Road Not Taken" is its intriguing ambiguity in its discussion of a most ambiguous topic, indecision.  For, it is often comforting for many to know that others share their angst about decision-making, both in the process and in the rue that follows:

I shall be telling this with a sigh
Somewhere ages and ages hence:

Purportedly written about his friend Edward Thomas with whom he took walks in Nature, an indecisive man who could not choose a path for fear another route might hold more beauty of flora and fauna, this poem is a facetious commentary on indecisiveness in situations that are not worthy of such indecision.

On the other hand, others interpret the poem metaphysically as a metaphor for life's choices and the regret that many feel for not having taken another direction in life, or the wonder about what if they had made other decisions and choices. At any rate, all readers can relate to the reflections of the speaker in Frost's poem.  Indeed, it is a poem that in one way or another touches all, whether humorously or seriously, and is, therefore, appealing.