People and excel dont always mix.
people who like numbers and systems and boundries like the world they create in excel.
People who think about hills, and flowers, and clouds, dont tend to like other peoples spreadsheets becuase they are not in control. The reality is they are not capable of building up a spreadsheet they could trust themselves, so have a hard time using something out of their control... My experience anyways...
I use excel all the time, but it is easy to make simple mistakes, then carry them through only to realise later, DOH! (just earlier i was doing a cumalitive summation, and forgot to dollar/anchor up part of the array, and the result was very confusing till i saw the error).