The Remix IDE that you have used so far is good enough for development and initial testing of your contract. For real-life contracts, you need to test your functionality against various parameters. Remix cannot create real (non-test) user accounts to transfer funds between them. You have no control over the configuration of the Blockchain created by Remix. You cannot even monitor the execution of the transactions.
Remix misses out on several advanced operations. Thus, we need to deploy our contract on a more sophisticated Blockchain that provides all these features. One such Blockchain is Ganache that you will learn about in our subsequent chapter.