Many of the spreadsheets I have made and worked on are used for reports. The layout of data is set up to be printed, so if it is a landscape report there are no blank columns or rows generally visible on screen. Thus, if there was a cell off where you'd have to scroll to see it, and especially if it was just a check that rarely went off, it'd probably be easily overlooked.
Most of the time if one of my checks went off, it meant the report wasn't going out, so I could make a cell on the report say Error or turn red (or both).
If you have checks, they should NOT be able to be overlooked, whether it is a tech or secretary or general data entry personnel, because at some point it will be you, the engineer, rushing to get a report out, doing it yourself instead of the regular personnel (who has of course become used to scrolling over and checking that little cell), and it is going to cause a problem.