Reply To: Just a comment for modifer in Blender 2.9
That is not true!
You must have done something wrong! Depending on what that is, that might (and probably will) get you into trouble later on!
Try to figure it out (check for ‘double Vertices’ and so), or post a link to your .blend file here in this thread (upload it to Dropbox, Google Drive, or any file-sharing service).