Because percepts are the result of free induction, they are unlikely to be false. Therefore, the sense of correctness is weakened by the absence of a context for falseness, (vis. the experience of pleasure is weakened if there are very few painful experiences and is most pronounced when the number of painful experiences is 1/2 of the number of pleasurable ones. (Pleasure cannot be sensed as pleasure in the total absence of pain. But if the pleasure/pain ratio is 1:1 neither is favorable, i.e. cannot be assigned the term pleasure in the sense of 'preferred'. See index "Nature of Existence-#Logical Principles- Preference and Distinction.)
The sensual and perceptual standards are utilized by natural selection for species reproduction. Stimulation of sex organs (which are provided with extra sensory receptors) causes consciousness to be concentrated. Concentration means that the object not being concentrated on 'disappears' from the attention of the concentrating entity. Those percepts most reinforced are the default states of concentration. That is, if there is nothing in particular to concentrate on, the act of concentrating will rest on those percepts most reinforced (important). These are the standards of pleasure and inductive correctness.
When all percepts except those two standards have disappeared from attention, orgasm occurs. That is, the entity experiences first the standard of pleasure then that of 'self' then again pleasure on the return to normal status.