I see it a lot, companies using Power BI for the wrong purpose. For example, using Power BI to deliver millions of rows in table format. As you may have experienced delivering millions of rows in Power BI can cause a very slow user experience.
The best use case for this power bi tool is to have more summarized data to display in graphical form. It’s not to say you should never use tables in a Power BI report, but your first focus should be how you can use the data you have in visual form.
Microsoft have developed the capability in Power BI to deliver this type of table data though in Paginated Reports. “Paginated reports are best for scenarios that require a highly formatted, pixel-perfect output optimized for printing or PDF generation”. With this in mind its still doesn’t mean you should slam the Power BI model with millions of rows.
Some may argue though that there is no problem with millions, if not billions of rows. But evidence can be seen here that people do struggle with performance. Microsoft say that soon Power BI will be able to query a trillion rows!
Kinetica have claimed to make this real easy, but I think that many companies would not have the budget to invest in massive parallel computing