Critics and poetry lovers have offered multiple and varying perspectives on this poem. Its complex theme makes it one of the most misinterpreted poems. The speaker’s choice of the road "less traveled by" can also be interpreted in more than one way.
The following explanations are based on the autobiographical and allegorical reading of the poem:
This piece was first published in 1916. Robert Frost had shifted to Britain in 1912 and stayed there till 1915 before moving back to the US. It has to be remembered that Frost wasn’t a name to be reckoned with in the literary field until he returned to the US. Till then he had tried out several options to get settled in life. He started as a teacher; he tried to set up his farming business but after nine years on his farm, he remained unsuccessful. He got back to teaching in 1906. In 1912, he took a big decision to shift to Britain with his family. He did so with the hope that his work would be appreciated there and sooner or later he might be another literary luminary. He believed that this decision would make “all the difference” he looked forward to.
Moving to Britain to build up a literary career wouldn’t be called a prudent decision in his times. It certainly involved a lot of risk. Where this option appeared promising to the poet, it could have make things worse for him as well.
So, his decision to move to the US might be the road less travelled by in the poem. He takes up this unusual decision with the hope to establish himself as a poet.
This poem can be read as an allegory of the path of human life. Life always offers us two ways to do things - right and wrong. It is universally believed that the wrong path appears to be luring and comfortable while the right one seems difficult and thorny. The end results would however be just the opposite. Still only a few take up the right path which is "the one less traveled by." A man of strong character, the speaker can be said to be one of those few who choose the tough but right path knowing the challenges awaiting them ahead.
Third, the speaker may be described as a man who doesn't follow the herd. Instead of joining the crowd and following suit, he would prefer to be considered as one with individual personality with originality of thought. That might be the reason he takes the road “less traveled by.”