When the season comes to its ending weeks, with very last matches, 3 points in difference are big enough to secure a title. The season in reality still has many remaining matches and 3 points are not too much and not safe for Barcelona to make sure they will lift the league trophy. At least if they can make diference to not only goal difference but point difference with 3 points, it's better.
Barcelona still have best advantage in the title race and they are controlling the race, but Real Madrid won't give up and there are potentiality of rank changes in La Liga. Atletico Madrid have most disadvantage but they won't give up and will fight best first and wait for results of Real Madrid and Barcelona in coming weeks.
As the final weeks of the championship approach, 3 points of difference can make the difference in winning a title. Barcelona still has the advantage but Real Madrid does not give up. Atletico Madrid does not give up and waits for the result of Real and Barca.
Let's say we are in a situation where there is a lot of uncertainty and therefore this keeps the fans glued to their seats to see how it will end.
Those are the three main Contenders in Laliga this season and I believe that at this point, they'll be very careful not to lose any chances, especially Barcelona and Madrid, Atletico has shown toughness this season but they're not very tough enough since Real Madrid and Barcelona still got their way with them when they met. Barca at this point needs to be extremely careful and hope that none of their star players get injured they can't afford to give Real Madrid the slightest opportunity cause I see Madrid are waiting patiently to strike at the advantage given to them by Barca, got for Barcelona that they still have an outstanding match that would put them 3 points ahead of Madrid and they need to win. These few weeks are going to be interesting and I can't wait to see how it goes.