The Vilna Gaon on Human Counsel and Divine Will

The core explanation begins with the Gra (Mishlei 19:21), who reads the pasuk as teaching that a person forms many plans about how and when to act, yet only the counsel that Hashem places in his heart is the one that will ultimately be fulfilled.

Even Sheleimah 4:17 extends this by noting that a person's initial impulse of will feels pure and upright to him, but only Hashem truly discerns the depths of the spirit and knows whether that first impulse was free of any ulterior motive, so that one cannot rely on human intellect alone to validate his own plans.

Even Sheleimah 4:17 warns that even a small hidden root of bitterness in the heart, if followed as though it were simply the honest path, can cause a person to fall from great heights without his own awareness, reinforcing the idea that human counsel is inherently unstable compared to the counsel that comes from Hashem.

Makkot 23b-24a does not address this pasuk in Mishlei or the theme of human versus divine counsel at all, but rather discusses the count of the 613 mitzvot and their correspondence to the days of the solar year and the limbs of the body, so it does not bear on the question asked.