The metadata for each layer in our GIS library displays "Date/time last touched". This may or may not be useful information.
The touched date/time is the most recent date time found on the files for the layer's maintenance format. That is, it's the latest date/time on the Coverage files, Shapefile files, or the Enterprise GDB feature class as specified in the "Maintenance format in our library" field.
The "touched" date and time may or may not represent a meaningful update to the data content. It means that something was done to the files on that date, be we don't know what.
The touched date may change as a result of:
There are even programs that will do nothing but "touch" files with the sole purpose of changing the file's date and time and doing nothing else. We don't routinely use such programs.
"Date/time last touched" may be a good indicator of a recent data content update provided it's evaluated in context and makes sense. However, there is no way to be sure there was a meaningful content update on this date. On the other hand, we can be rather certain that a layer has not been updated since the touched date. That is, we know the last update was on or before the touched date and it hasn't been updated since.