I agree but also believe a spell will work as fast as your intentions are good and yeah if you don't put efford into it it may back-fire spells aren't ment for people to lay back just cast and have it easy some spells take a lot of time and a lot of effort .And if you need a quick spell ( for emerginecy) I heard fire spells are the fastest. You do your spell write it down and burn it over a open fire not indoors !
I write my own spells in four to six line rhymes, burn after casting and spread cooled ashes on the wind or down a stream to carry it physically on the elements. Sometimes it is instant sometimes it takes months and sometimes I must recast.
A cleansing or protection is the only time I got instant results. After a cleansing you should feel a difference, if not you need to do another. If you mean a wealth spell then a minute later someone knocked on my door and gave me a check, no, spells don't work like that. [Would be neat though lol]