When I run this code, I get an error="Type mismatch." How come?

Public Sub HideSelectedSheets()
Dim Wsh As Worksheet
For Each Wsh In ActiveWorkbook.Sheets
If UCase(Wsh.Range("G1").Value) = "HIDE" Then
Wsh.Visible = xlSheetHidden
End If
Next
End Sub

Thank you.

John Wirt