hit-or-missadjective
/ˈhɪt·ərˈmɪs/also hit-and-miss, /ˈhɪt·ənˈmɪs/as likely to be bad as to be good, esp. because of not being planned or organized well:
The service you get in these big stores can be hit-or-miss, depending on the salesperson you talk to.