This may be a very simple question, but I couldn't figure it out on my own.
I stumbled upon this when comparing a string to individual collection items (all being strings themselves).
Consider the collection:
{"mom","dad","sister","brother"}
for some reason in my workflow there is 'a' special token behind "brother" and I'm not sure which one. So I added a block to print out each collection item and the string we're comparing it too. And in the history log it's clear that there is a significant difference.
(worth mentioning: the collection is build using a regular expression on a choice field splitting on ;# because it seems that's how SharePoint keeps choices separated)
When printing behind the last collection item (in this case "brother") we find the following:
<br><br><br><br><br><br><br><br> 
next to "WHY?" I'd like to know how to solve it.
(Right after writing this I'll be trying the inline 'trim' function, and if that solves it, great, but I still would like to know why this is happening)