How did the term "worthless" come by its current definition?
Solution 1:
Your definition would be wrong. The suffix -less means:
1 (forming adjectives and adverbs from nouns) not having; free from.
‘flavourless’
‘skinless’2 (forming adjectives and adverbs from verbs) not affected by or not carrying out the action of the verb.
‘fathomless’
‘tireless’Origin
Old English -lēas, from lēas ‘devoid of’.
Note that the origin given for the word less is different.