IEEE 754 just has unintuitive properties.
Kahan (the "father of IEEE 754") has a rant (among many others) about Excel as well, and how it tries to hide some of the floating point complexities more or less successfully:
Floating-Point Arithmetic Besieged by “Business Decisions”
https://carolomeetsbarolo.wordpress.com/2012/07/20/catastrop...
Or:
"OOPS XL Did It Again"
https://carolomeetsbarolo.wordpress.com/2014/06/22/oops-xl-d...
From the Wikipedia article:
"Although Excel can display 30 decimal places, its precision for a specified number is confined to 15 significant figures, and calculations may have an accuracy that is even less due to five issues: round off,truncation, and binary storage, accumulation of the deviations of the operands in calculations, and worst: cancellation at subtractions resp. 'Catastrophic cancellation' at subtraction of values with similar magnitude."
julia> 1e20 + 1000 - 1e20
0.0
julia> 1e20 + 10000 - 1e20
16384.0
Python 3.9.6 (default, Jun 28 2021, 19:24:41)
>>> 1e20 + 1000 - 1e20
0.0
>>> 1e20 + 10000 - 1e20
16384.0
https://docs.microsoft.com/en-us/office/troubleshoot/excel/f...
"Align numerical precision Excel 2013 and R"
https://stackoverflow.com/questions/39531655/align-numerical...
"Numeric precision in Microsoft Excel"
https://en.wikipedia.org/wiki/Numeric_precision_in_Microsoft...