Hi Terry,
We did that for the sake of readability. Our currentScene variable represents our idea. If we take a look at this code in a couple of months, we’ll immediately know what the purpose of the next line is: LoadScene loads currentScene.
The one-liner could require some guesswork. GetActiveScene() might make sense but what about buildIndex? Maybe we will have to look that up to understand the code in the future.
I recently found this webcomic which sums the idea up pretty well, in my opinion:
Did this make sense? 
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- Forum User Guides : How to mark a topic as solved