localization problems

I got the POEditor for po and mo files, but WP is getting string translated from core localization.

eg:

I have on my plugin this:
$btnFinish=__(“Finish”); //on line 141

my mo/po file:

#: file.php:141
msgid “Finish”
msgstr “It’s finished” – but in anoother language

WP give me msgid “Finish” from localization languaged not from my mo/po file…

I think i’ll use php define statement :p

Cheers