少不了
shǎo bu liǎo · HSK 7
cannot do without
少 (few) + 不了 (cannot finish/can't) = so few it can't be done without it — indispensable
少不了 literally stacks 少 shǎo few/lacking + 不了 bu liǎo cannot manage. Reading it as cannot afford to lack gives cannot do without; the are bound to be many sense flips it: you can't end up with too few.
少 — 小 (small) + 丿 (slash stroke)
Originally a pictograph showing four small dots or grains, suggesting 'few' or 'small in quantity'. Over time it became distinguished from 小 (small) by adding a downward stroke. The core meaning shifted toward 'few' or 'little in number', while 小 kept the sense of physical smallness.
不 — single pictograph; bird flying upward
Originally a pictograph in oracle bone script, traditionally interpreted as a bird flying up toward the sky and unable to come down, suggesting negation or refusal. Over time it became the standard negation word in Chinese, used before verbs and adjectives to mean 'not'.
了 — pictograph of swaddled child with no arms
了 originally depicted an infant wrapped in swaddling cloth, with the arms hidden or bound — a variant of 子 (child) without the arms. From 'finished wrapping' it extended to mean 'completed' or 'finished,' which is its main modern grammatical use as an aspect particle marking completed action.