SPOOL RIDDLE - Which way will it roll?

I first heard this riddle during a talk by Veritasium. Thanks to Derek for it. If you heard the riddle from Derek first too, do you remember the answer? Sad story: I filmed a collaboration with Derek asking him some other riddles and all the audio was unusable. Tragedy! It really was too bad because I almost got him on camera saying he hates riddles. Nearly exposed!