Marco Russo contrasts two functions for us:
Writing explicit type conversions is unusual in DAX, because most of the time the implicit conversion happening between different data types in an arithmetic expression provides the results you wanted. However, you might want to enforce a type conversion for different reasons: to round a number or to make sure a certain calculation is always approximated the same way. In particular, the conversion to an integer number can be obtained using different techniques – sometimes with small differences which in borderline cases might produce different results.
What we examine in this article is the difference between two techniques to convert a number to an integer: INT and CONVERT.
Read on to see the differences, including where things break down for INT.