Because excel files are the lingua Franca of the corporate world. Much easier to share an excel file with the numbers formatted to HR/finance/management expecta

Because excel files are the lingua Franca of the corporate world. Much easier to share an excel file with the numbers formatted to HR/finance/management expectations and a few graphs (which they can modify to their liking if necessary), than a word file with embedded graphics and tables (which they can’t change so they’ll ask you to redo the graphs in puce or whatever). Or god forbid a jupyter notebook... FWIW I worked once with a network graphing tool for a fairly involved HR topic (mapping out all possible career paths within an engineering department) and I spent half my time learning the tool, and the other half exporting images and importing them in PowerPoint.