rough, unsmooth - having or caused by an irregular surface; "trees with rough bark"; "rough ground"; "a rough ride"; "rough skin"; "rough blankets"; "his unsmooth face"; "unsmooth writing"

unstable - lacking stability or fixity or firmness; "unstable political conditions"; "the tower proved to be unstable in the high wind"; "an unstable world economy"

difficult, hard - not easy; requiring great physical or mental effort to accomplish or comprehend or endure; "a difficult task"; "nesting places on the cliffs are difficult of access"; "difficult times"; "a difficult child"; "found himself in a difficult situation"; "why is it so hard for you to keep a secret?"