The bads about griefing:

U may wreck something someone has spent hours building and placing the blocks in the perfect spot and you think it's fun to destroy parts or the whole thing yet u may hate it when people grief u

U only grief when there offline rarely when there online

U destroy creations made by mod admin ops that they made for themselves someone else or a creation to benefit the server

U join people's faction so u can do /f home to get to the factions base u are in and grief and steal stuff