Apple is rank as the world's most valuable brand, on various metrics. Nevertheless, Apple's recent revenue report was $74.60 billion with $18 million in profit for a single quarter,which was considered the largest earning of any company ever. Apple is the most profitable company when compared to several other companies.
The word "Ever" can mean multiple things, but even in all these definitions, Apple is not the most successful company. If "ever" means the present day, it's incorrect as Microsoft once peaked above Apple. If it means, the recent five years, then we can say yes. However, we have to look at all of history, and there are plenty of companies, especially monopolies, that were more successful. Some examples include US Steel, Standard Oil or the East Indian Trading Company. Thus, Apple cannot be considered the most successful company ever.
Apple would only be the most successful company if it didn't have any problems or issues. There are some customers who refuse to use their products because of their hatred for the company and it's products. This does not spell most successful to me. Most of their customers are clueless about tech devises and only use Apple products because they are user friendly.
At one point in history, the Dutch East India Company was valued at over 7 trillion dollars when adjusted to modern currency. Apple, by comparison, is not even worth 1 trillion. While Apple is absolutely huge by today's standards, it is nowhere close to being the most successful company in history.
Apple isn't quite the most successful company ever. They may be one day. It kind of depends on how you define "success" but no matter how you do Walmart has them beat by a long shot. Even to say they are the best "computer company" ever might be wrong because Microsoft is on up there with them.