Avengers: Infinity War - What Does The Ending Really Mean?
2. Ant-Man And The Wasp Might Be Super Important
Sticking Ant-Man at the end of Phase 2 made for a nice little palette-cleanser coming off Avengers: Age of Ultron. The movie was lighthearted, funny, and had low stakes (and Paul Rudd, which always helps). Although not the biggest hit, it worked well enough that Marvel are attempting to repeat the trick again, with Ant-Man and the Wasp coming out just a couple of months after Infinity War.
However, based on the events of this movie, Ant-Man and the Wasp could be really quite important in the future. Although it's set to take place before Infinity War, we know it'll be diving deep (literally) into the Quantum Realm, which in turns opens up the doors to the multiverse for the future of the MCU.
With the characters from that movie set to be in Avengers 4, and a fashion needed to bring heroes back and/or find a way of defeating Thanos, then the Quantum Realm, rather than the long-rumoured time travel (since the Time Stone is now in the Gauntlet), could be a means to that end.