A Reddit user named, Jester651 had shared an infographic which explains each Infinity Stone’s role in the Avengers: Infinity War’s ending.
The Infinity War movie had made it clear that in order for Thanos to actually wipe out half of the universe, he will need to wield the power of all the six Stones. It is not explained why he needs all of them. Considering the elements of existence that each stone exerts power over, we can assume that just a few are necessary to complete the task. This infographic has a few logical explanations which the Avengers had not explained:
His snap was pretty devastating and maybe this is why the fans were not so concerned about asking why. Here, we have a very interesting way to look at the powers of the Gauntlet. Wiping out half of the world not a small feat. It makes sense that this task required immense power.
This is the synopsis for Avengers: Infinity War:
“As the Avengers and their allies have continued to protect the world from threats too large for any one hero to handle, a new danger has emerged from the cosmic shadows: Thanos. A despot of intergalactic infamy, his goal is to collect all six Infinity Stones, artifacts of unimaginable power, and use them to inflict his twisted will on all of reality. Everything the Avengers have fought for has led up to this moment – the fate of Earth and existence itself has never been more uncertain.”
Directed by Anthony and Joe Russo, the film stars Robert Downey Jr., Chris Hemsworth, Mark Ruffalo, Chris Evans, Scarlett Johansson, Benedict Cumberbatch, Don Cheadle, Tom Holland, Chadwick Boseman, Paul Bettany, Elizabeth Olsen, Anthony Mackie, Sebastian Stan, Tom Hiddleston, Idris Elba, Peter Dinklage, Benedict Wong, Pom Klementieff, Karen Gillan, Dave Bautista, Zoe Saldana, Vin Diesel, Bradley Cooper, Gwyneth Paltrow, Benicio del Toro, Josh Brolin, Chris Pratt, Danai Gurira and Letitia Wright.