Rank Placement

So Season 6 started and I thought it was a new chance for me to start fresh and be in a higher ranked then I was previous season (bronze). Well once the season began I was excited and was doing and well I ended up winning 6 out of 10 games and well once I saw that I was placed in bronze V I was very disappointed because I recall when I first played ranked and went through the whole placement process I was put in bronze 3 for winning 4 out of 10. I was also told by a fellow friend that he won 8 games and lost 2 and was also placed in bronze v. Can someone please explain why I'm in bronze v?