The repair process takes too long because it has to verify all the files. In most of the cases, the files are verified against a MD5 hash. Since FIFA 11 uses large game files, the process takes a while. The installer calculates the MD5 hash of the file and then it compares it to the one in the database, then it builds a list with files that need repairing. The process could take from a few minutes to maximum an hour or so.