Before analysing a list anyone else produced, look at its shortest entries. It takes ten seconds and routinely changes what you do next.
What turns up at the top
Single letters, stray punctuation, empty-looking rows, two-character fragments, and occasionally a column header that came along with the data.
Why the top of the list is diagnostic
Junk concentrates at the extremes. If the shortest twenty entries are all garbage, the export was malformed and cleaning it is the first task rather than an afterthought.
Check the longest end too
Sorting the other way exposes merged fields and runaway values. Between the two ends you will have found most of what is wrong with a list in well under a minute, before any of it reaches a report.
Try it: Sort by Length (Shortest First) on SeoWolf's Notepad.