properties - Why should a C# property getter not read from a DB?

Question

Some of the answers and comments to this question: Simplest C# code to poll a property?, imply that retrieving data from a database in a property's getter is Generally a Bad Idea.
Why is it so bad?

(If you have sources for your information, please mention them.)

---

I will usually be storing the information in a variable after the first "get" for reuse, if that influences your answer.

Answer 1

Because retrieving data from a database could cause any number of exceptions, and property getters, as a rule, should never throw exceptions.

The expected behavior of a property getter is just to return a value; if it's actually doing a lot more than that, it should be a method.

Microsoft's guide for Property Design explains the reasons: https://docs.microsoft.com/en-us/dotnet/standard/design-guidelines/property