In the premier league there are no weak teams, even teams from the bottom of the standings can fight back and draw or even beat the favorite.
Today Liverpool almost lost on the team ranked 18th in the league and just lucky that Liverpool was able to keep the victory over Nottingham.
So Arsenal tried, but Southampton were also fighting for survival, which gave them motivation.
3 draws in the last 3 games is not the best result for Arsenal, but there were no losses either. They have a match against City ahead where they can show their character and see if Arsenal are ready to become the champion of the English Premier League this year.
Regarding 3 draws in 3 consecutive matches, then I think that is one proof that Arsenal are not ready to win the Premier League title this season. Manchester City are the team most likely to win the title this season although Arsenal still lead a few points clear in the standings. If Manchester City manages to beat Arsenal at next week's meeting, then Arsenal will likely fail to win the title.
Manchester City have two match in hand that they are actually very likely to win if form can be maintained. The game versus Arsenal will really decide his title chances, so it's too important to win. After all Manchester City are playing at home, so they have to be very motivated to win it.