He just made this choice moments after he was setting up Obi-Wan for payback, with the clear intention to put Obi-Wan through everything Vader himself suffered after their duel on Mustafar. Considering that was dismemberment followed by burning alive without quite being allowed to die, the terror of being hunted is distinctly negligible.

He also seemed to be teleporting like a slasher movie villain, who never runs, but is somehow always right behind people who are running, just like Reva somehow getting to the end of the escape tunnel before Leia, without passing her.