I generally don’t recommend switching perspectives in a novel. The main reason is that unless there is a specific reason to tell more than one perspective, it may muddle the story or make it so that you’re writing two separate stories in the same novel. If the separate stories are not especially connected, it can make the novel feel lopsided or distracted.
Of course there are instances where it works. My favorite example is Station Eleven by Emily St. John Mandel. Structurally, this novel is wild. It comes together so beautifully and left me amazed. The story jumps around in time, through the lives of loosely related characters. Other examples that I love include The Sound and the Fury and As I Lay Dying both by William Faulkner. In both instances, most characters and points of view are members of a family, or related in a way to the central family the story is about.
The Sound and the Fury is actually a great example to start with. I wouldn’t say there’s just one main character in this novel, but a collection of them. You get four points of view around the downfall of the Compson family. For this reason, the switching points of view does not detract from the novel, but perhaps even further points out that this story does not fully belong to any one of the four point of view characters.
There are other practical instances where switching perspectives makes sense, like in Stephen King’s It or Maggie Stiefvater’s The Raven Boys. I know these are two very different examples, but they both happen to be told through multiple points of view, following a group of friends. In both examples, there isn’t exactly one protagonist, but again, a collection of them. This group of friends more often than not has the same goal or aspirations. The different characters may be involved in different, individual subplots, but for the most part, the central plot line is shared by all characters.
Another instance where it makes sense to switch points of view is in a romance. The two romantic leads may share the story when both are privileged with their own points of view. One successful example of this is Rainbow Rowell’s Eleanor & Park. Of course, this is not necessarily always a recommended tool. Jane Austen’s Pride and Prejudice would have been ruined had we understood Mr. Darcy’s intentions from the start. It’s examples like this where the limited perspective of just one character allows for Elizabeth’s misunderstandings to be the reader’s misunderstandings.