Mangled cluch steel

Hello peeps
Whilst refitting clutch plates/steels i noticed the bottom steel was worn/burred badly on the tabs. The other 3 steels seem to been virtually unaffected. Anyone think of a reason this should happen. All parts fit nicely into sprocket and the clutch was working ok.
Cheers Super
Whilst refitting clutch plates/steels i noticed the bottom steel was worn/burred badly on the tabs. The other 3 steels seem to been virtually unaffected. Anyone think of a reason this should happen. All parts fit nicely into sprocket and the clutch was working ok.
Cheers Super