re: #740 BryanS

from [Link: www.merriam-webster.com…]

Main Entry: hone in
Function: intransitive verb
Etymology: alteration of home in
Date: 1965

: to move toward or focus attention on an objective (looking back for the ball honing in — George Plimpton) (a missile honing in on its target — Bob Greene) (hones in on the plights and victories of the common man — Lisa Russell)
usage The few commentators who have noticed hone in consider it to be a mistake for home in. It may have arisen from home in by the weakening of the m sound to n or may perhaps simply be due to the influence of hone. Though it seems to have established itself in American English (and mention in a British usage book suggests it is used in British English too), your use of it especially in writing is likely to be called a mistake. Home in or in figurative use zero in does nicely

What part of “mistake” do you not understand?