I do not know that much about Crypto Currency. But as far as I understand:
- Whenever a new block is mined a list of transactions is executed. This means transaction speed depends on the rate with which new blocks are mined. What is that rate for Monero?
- Difficulty of the proof of work algorithm to mine new blocks is adjusted to keep the rate as constant as possible
2 minutes on average
That is quite fast actually. I think fast enough for an online shop, and maybe for a coffee shop. But not for a high throughput Walmart like store.