Parasuramani (1985) loodud mudel selgitamaks viit lõhet, mis põhjustavad lõhesid kliendi poolt tajutud kvaliteedi ja tegelikkuses püüeldava kvaliteedi vahel, a model, highlighting the main requirements for delivering high quality service which identifies five gaps as causes for unsuccessful service delivery has been formulated by Parasuraman et al (1985)