Continuing in a series of insights and observations in the Proverbs...
Her feet go down to death;her steps follow the path to Sheol; she does not ponder the path of life;her ways wander, and she does not know it.
In verse five, the author states that the feet of the adulteress "go down to death, her steps take hold of Sheol," with the consequence (in verse six) that "her ways are unstable [but] she does not know it."
Like the "lip" motif in verses one through three, this description of the adulteress’ feet and "ways" is set over against the advice (or wisdom) given by the author at the end of the previous chapter. There, the author has already admonished the reader to "watch the path of your feet," with the consequence that "all your ways will be established."
So the author appears here to be contrasting 1) the wise man’s self-knowledge, mindfulness and attentiveness to his lifestyle and careful, intentional consideration of the effects of his behavior on his life to 2) the adulteress’ lack of self-knowledge and inability or unwillingness to "ponder the path of life."
The wise man’s ways are "established" as a result, while the adulteress’ ways are "unstable". Since stability is much to be preferred over instability, the truly good option is here obvious.