Rituals comfort, as they are formalized routines and have predictable results. In an uncertain world, life often follows such routines simply because of the comfort predictability brings. Change, even change for the better, brings anxiety. Thus the lowly crab may pause before entering a dark crevasse in a rock, routinely, finding that this extra moment to scan the path ahead comforts.
Done repeatedly, a routine becomes ritualized. Humans speak of rituals in the context of religion, as religious rituals, but their lives are fairly riddled with rituals that occur daily, weekly, or in any case frequently. Start with the morning routine. Why should the newspaper be read routinely over coffee and not at other times during the day? Someone used to this ritual finds a morning cup of coffee without the news lacking, feels uncomfortable, and may even dress and leave the house in order to buy a paper so the ritual will be complete. Males are expected to open doors for females, a rule established due to the expectation that the woman may be with child, or have an infant in her arms, but this routine is frequently ritualized so that a burdened male will put down his parcels to open the door for a free handed and hale female.
Rituals may start as routines, but become rituals when they become absolute rules. Where the ritual is self imposed, as in obsessive compulsive behavior, any argument over the nature and necessity for the ritual is with oneself. Religious rituals develop to assist the religious elite in maintaining control over their flocks. There can be no encroachment of the rules, as first a ritual must be broken. Controlling rituals are very much in use within Service-to-Self alien groups, so much so that almost every motion is within some ritualized behavior. One might imagine that such an activity as piloting a space ship would be procedurized, but unlike what humans might expect, an alien pilot in the Service-to-Self orientation may not break the routine, even for good cause. To change the ritualized behavior would be stepping outside of the control of the overlords, who would rather lose a ship than lose control.