"In general, Bitcoin transactions usually take from one to one and a half hours to complete."

A friend owes me money and he wants to pay me in BTC, so I gave him my BTC wallet address.
He makes a small payment every day and there have been 8 payments in eight days.
However, when I check the transactions, each one says,


"Be aware, that this transaction has not yet been confirmed."

I thought BTC was fast and quick. Why is it taking so long? Is there foul play?