When it comes to preparation I believe in the six P's. Perfect Preparation Prevents Pxxx Poor Performance.
I am trusted to capture unrepeatable, fleeting, moments in time. No second chance, no dress rehearsal. Imagine this - "Sorry Mr & Mrs newlywed I missed your first kiss because the camera battery ran low, I didn't pack a spare". Or, "I couldn't photograph your first dance because I forgot my flash and it was too dark to shoot without it". The thought of missing those moments due to a lack of preparation is my nightmare.
A typical wedding involves a day of shooting/travelling and a few days of editing, most couples do realise this. However, unseen by all, are the hours of preparation. Charging camera batteries, formatting memory cards, cleaning and checking cameras and lenses. Packing kit against a check list. Is the car OK, fuel, tyre pressures, RAC paid for and up-to-date? SatNav programmed, group shots list packed, suit clean and pressed, shoes polished. Food and water for the day, purchased and packed? And on, and on....... There's a good day or so in preparing for a wedding on top of meeting with the client, website administration, the wedding day, post wedding admin and editing.
it's a huge amount of work, and I love it!