Is my checkout process too long? How many steps should a good checkout process have?

I've been running my online fashion boutique for three years now, and lately, I've become increasingly worried about our checkout process. Our conversion rates have been stagnating, and I suspect our checkout might be the culprit. Every time I look at our analytics, I see a significant drop-off between 'add to cart' and 'purchase completed'. It's frustrating because customers are interested enough to select items, but something in our checkout flow is making them abandon their purchase. I've gone through the process myself multiple times, and while it doesn't feel excessively complicated to me, the data tells a different story. My team keeps arguing about how many steps are necessary—some say we need detailed information for a smooth experience, while others believe we're creating unnecessary friction. I'm particularly concerned about mobile users, who I know have even less patience with complicated checkouts. I want to understand the ideal number of steps, what information is truly essential, and how I can streamline the process without losing important customer data or compromising security. This isn't just about reducing steps; it's about creating a checkout experience that feels smooth, trustworthy, and effortless.