If the serpent bites before it is charmed, there is no advantage to the charmer.
The scope of these verses is to keep subjects loyal and dutiful to the government. In Solomon's reign the people were very rich, and lived in prosperity, which perhaps made them proud and petulant, and when the taxes were high, though they had enough to pay them with, it is probable that many conducted themselves insolently towards the government and threatened to rebel.
Commenting on Ecclesiastes 10:4-11
Surely the serpent will bite without enchantment,.... See Jer 8:17. Or rather, "without a whisper" (t); without hissing, or any noise, giving no warning at all: so the Vulgate Latin version renders it, "in silence"; some serpents bite, others sting, some both; see Pro 23:32; some hiss, others not, as here; and a babbler is no better; a whisperer, a backbiter, a busy tattling body...
A "serpent will bite" if "enchantment" is not used; "and a babbling calumniator is no better." Therefore, as one may escape a serpent by charms (Psa 58:4-5), so one may escape the sting of a calumniator by discretion (Ecc 10:12), [HOLDEN]. Thus, "without enchantment" answers to "not whet the edge" (Ecc 10:10), both expressing, figuratively, want of judgment.