Copy and paste is an alternative to uploading data for smaller data entry tasks and is not recommended for more than a few dozen changes or additions, as the time to complete the task increases as more rows of data are pasted.
Copy and paste is an alternative to uploading data where data validation does not need to be as extensive.
Copy and paste highlights simple cell-by-cell errors , whereas uploading has error logging features that create an error log file. The log can be printed or saved for reference, or used for trouble shooting the errors in the upload files.