I used to work at a company where, under duress, I had to push tableau to its limits. My company spent hundreds of thousands of dollars on it. The main use was to provide reports on the data created by the application we sold.

It would be great if it just stayed as a better version of the excel chart maker. Instead, it was seen in my company as a way to replace programmers. All of these types of applications have the same flaws:

They sell a dream that you can turn a complex task that requires experts, into a simple task that anyone can do. In reality, you either have a simple application that doesn't do much, or an extremely complex application that still doesn't offer the performance and flexibility of just using an expert.

You end up creating a programming via drag and drop application that is more complicated to learn than actual programming. You replace general programmers with useless tableau specialists.

It took the tableau experts weeks to do what a programmer could do in days when complex requirements came up. Most requirements were complex.

Tableau Server is very, very slow and requires massive resources to run.

Tableau had to run the full, unfiltered query so that it could generate filter lists with all of the possible options. This query was often too large to run.