Prior to Al Gore inventing all the internets, most states used the costs of performance as the method to determine nexus. If your butt was in Colorado and you provided a service to people in California, the costs of performing the service would be in Colorado and therefore you would not have nexus to California. You would only be subjected to Colorado income taxes.
Given the latest Bloomberg survey, there is a growing minority of states that are using the market-based approach. This can be loosely defined as the assignment of revenue based on the location of either
Consider a web server. As of 2016, 38 states plus the District of Columbia and New York City would consider a web server physically located in their taxing jurisdiction as enough of a presence to find income tax nexus. And most would find sales tax nexus as well. Wow. 38 is a high number, and it is old.
There is an executive summary for 2018 available from Bloomberg, and it is only 20 pages (nice!)-
Taxpayer's Comprehensive Guide to LLCs and S Corps : 2019 Edition