Either out of pure fascination or forcefully, or for no reason or both.
Tell us, your level of motivation and the reason and maybe provide some ways you learn.
To me, Mexican Spanish.
Always did have obsession with Mexican culture, through cartoons, games, movies, and the list goes on. Spanish always snuck in and keeps sneaking in, into mainstream media. Coupled with the fact, that my love for Spaghetti Westerns are the by-product of this fascination result.
Now why MEXICAN and not Spanish? Cause I don't understand Castillian, "B" and "V" both sound like "B", same with "Z" and "S", both sounding like "S". And don't get me started on "LL", this letter suffers from Mandela effect, I swear, somebody has planted inter-dimensional portals all over my house...
Oh, and it has no 2nd person plural
How I learn?
Started with textbook, 'til dropped it in favor of the Internet's online dictionary and verb conjugations + Memrise + Listening to Spanish covers/songs.
It was tough as cojones in the beginning, but got easier as time went on. Like playing a proper video game, with brain simulating challenge and difficulty. So follow you dreams! Keep on goin'! If you ever had any language to learn, in mind.