Etabs Mass Summary By Story Better Hot! -

By default, ETABS does not automatically include all gravity loads. It uses the Mass Source defined in Define > Mass Source . If you skip this, the program uses only the self-mass of elements—which will dramatically undervalue your seismic weight.

Engineers typically search for a "better" version because they encounter these three specific failures:

The rotational mass about the Z-axis.

Here’s a professional, engaging post you can use on LinkedIn, a blog, or an engineering forum like Eng-Tips.