WWE Raw star and a former four times WWE World Champion Seth Rollins who is also a former two times WWE Intercontinental Champion recently talked about a potential Shield reunion. He said that another Shield reunion would not be possible before getting inducted into the Hall Of Fame.
The Shield made their first appearance during the Survivor Series pay per view event of 2012 during the main event of the night where CM Punk defended his World Championship against John Cena and Ryback. Seth Rollins, Roman Reigns and Dean Ambrose where the three members of this stable.

Seth Rollins Is Not Hopeful About A Shield Reunion
All of these three individuals were projected as the future main event stars. The Shield were the biggest attraction of WWE during their time. They had always been on the mid card title pictures since their debut. But really they were projected as World Champions before splitting up.
At first they work as a heel stable, but later they turned babyface and till the end they worked as faces. At the 2014 Royal Rumble match, Roman Reigns broke the record of eliminating most number of individuals in a single Royal Rumble match, which quite clearly indicated towards a future main event push for him. On the same year WWE decided to break the stable and push the wrestlers as singles stars.

Seth Rollins was the star who betrayed their partners during an episode of Monday Night RAW and since then they started working solo. Before splitting up, another legendary stable Evolution reunited to give them their final push. After they split up, all of them turned out to be the future World champions, however, Roman Reigns had to be the most successful of them all.
Seth Rollins who is also a former two times WWE Intercontinental Champion recently spoke to Digital Spy where he talked about a potential Shield reunion. He said that another Shield reunion would not be possible before getting inducted into the Hall Of Fame. He said;

“It wouldn’t look the way you want it to look. It wouldn’t be like the old days in The Shield, it would be a different animal. I think we’re all just too big stars with too big personalities at this point. We needed each other back then and now none of us need the other one. We’re at a point where we’re all standalone stars on a different level.”
“So to have to kind of minimize that to fit into each other’s molds, I just don’t see it ever happening again. I think it would look a whole lot different than the next time you see us together. The next time you see us together it’s going to be when we’re inducted into the Hall of Fame. That’s going to be it.”