Standard objects and Big Objects are separate kinds of database entity. Big Objects are custom objects you can create to store massive amounts of data, while accepting certain limitations on your ability to query and manipulate those records in exchange.
What you're referring to is Large Data Volumes. Large data volumes in non-Big Object Salesforce objects, such as Asset and Order, demand careful consideration of your architecture, querying and reporting strategy, and automation to ensure your org remains functional and performant. The document linked here is a good place to start understanding these concerns.
To quote from the linked documentation,
A “large data volume” is an imprecise, elastic term. If your deployment has tens of thousands of users, tens of millions of records, or hundreds of gigabytes of total record storage, you have a large data volume. Even if you work with smaller deployments, you can still learn something from these best practices.