Describe someone who chooses the worst option for doing the work

Solution 1:

I believe the idiom put the cart before the horse applies here.

Fig. to have things in the wrong order; to have things confused and mixed up. (Also with have.) You're eating your dessert first! You've put the cart before the horse. John has the cart before the horse in most of his projects.
_{The Free Dictionary by Farlex}

The more vulgar version of the same idea is ass-backward (or its synonymous alteration, backassward).

: ludicrously disordered : showing an arrangement grotesquely counter to the usual or workable <incompetents doing their work in an ass-backward way>
_{Merriam-Webster}

Solution 2:

Although not figurative nor nearly as descriptive or cool as the Persian idiom that you mention, telling someone that:

he’s/she’s/you’re going about it the wrong way

kind of captures the idea in a literal, yet slightly different and idiomatic way (I say “kind of” because “the wrong way” doesn’t necessarily mean “the worst way”).

See the example in the provided link (to Your Dictionary) under “Classic Dialogues" (and below):

Foghorn Leghorn: [So you’re looking for a husband?] Well, you're going about it the wrong way, sister. You don't bat 'em on the bean with a rolling pin. That comes later.