Ritual magic has many uses. If you find ritual magic stale, rigid and boring, you're probably doing it wrong.
The purpose of centring rituals is to quickly banish distracting mundane thoughts, leave behind any worries and stresses and centre the magician in themselves. They are also useful in magical defence against malevolent spirits and warding off unwanted magical manipulation from others. They are also sometimes referred to as 'Banishing rituals' although originally this term only referred to their usage at the end of a ritual.
Opening and Banishing Rituals
Centring rituals can be used to open and close a larger ritual. Sometimes their form for opening a ritual will differ from their closing form, perhaps reversed in some way, but this isn't always so. When used to open a ritual they serve the additional role of preparing the magical working space and marking the division from mundane time to magical time. In a group this means not getting distracted with chit-chat or who's turn it is to do the dishes.