having a strong possibility of being unsuccessful

dangerous, risky

likely to cause danger

hazardous, troubling

uncertain; risky

risky

(of a person) often changing one's feelings about another person

vacillating, blowing hot and cold

too easily upset or offended

impressionable

(of a person) often changing (in opinion, temper etc)

flighty, temperamental

uncertain; unsafe; depending on chance

tricky, doubtful

quickly or easily receiving impressions; (of feelings) easily hurt or offended; (of instruments) able to record or reproduce small changes

impressionable

caused by temperament; quickly changing one's mood

angry most of the time; moody

easily or quickly offended

easily offended

(of a person, action) deceptive; (of work etc) having hidden or unexpected difficulties

complicated, difficult

not safe

dangerous

not settled

bothered, upset

(of a person, condition) not stable

doubtful

varying; changeable; a quantity or thing (e.g. cost, temperature) that can change according to conditions

changing, changeable

(of a liquid) that easily changes into gas or vapour; (of a person, mood) changing quickly or easily from one mood or interest to another

explosive, changeable

wavy

doubtful, weak