The outcome of the poll is quite meaningless by itself, because there is no indication as to how many of the books were read by the voting population.
So, if only (say) 4 books were read and one of those 4 was voted for (and one was only supposed to vote for books that they'd read) then the book showing the highest number of votes is potentially only indicative of a book that has been read and considered the best by a small percentage of the overall voting population.
I abstained from voting, because the poll was changed from open vote to closed vote, even though I nominated a book for this (and every) period. So, there may be others who also nominated books and didn't vote because of the change. (Or didn't nominate books but considered that open vote was their preference)
For me this Best Book exercise has proved most fruitful in drawing out the books of each decade that I have now followed up on (and which I might never have come across otherwise).