I just went to my first bass lesson a couple days ago... I've been playing guitar for over 40 years but when I decided I wanted to bet GOOD at bass I knew enough that being a decent guitar player doesn't guarantee success as a bass player.
I decided I wanted bass lessons since I thought I needed to learn walking bass lines and such but didn't really consider that my RIGHT hand technique is the key.
My instructor had me play a simple four note pattern using the index and middle fingers to pluck stright ahead 8th notes. I was doing okay at a fairly fast BPM but then he slowed me down...

...I totally sucked and could not keep up a nice steady 8th note line.
I grabbed my guitar pick and... no problem... but using my fingers to pluck... YIKES!
My instructor laughed... all he wants me to do for the next couple of weeks is play along to SLOW drum patterns going through the modes and doing nothing but 8th noting...
My right hand is burning like a beeeyotch!!

But I'm already feeling it getting stronger and finding my right thumb rest/mute technique (which is another mind-fark for me!)
Hey its all fun!!
Good luck!!