I have always found the charms of a pretty woman ineluctable, a weakness that has often cost me dearly.
in (not, opposite of)#ex (out)#luctari (to struggle) (Latin)
IN (not)+ELECTABLE. that cannot be elected. you don't have choice to elect because there is no option hence you cannot escape from it. Suppose a course is compulsory in a particular semester. So you are unable to 'elect' another course. ineluctable -- in +luc (k)+table. So, a person will be lucky or unlucky in his work on a particular day as per his luck-table, he can't escape from it, it's unavoidable.