Maintenance free

The markings showed Feb 2013 and it is now Nov 2014 so thats about 1 yr and 8 months. Normally a car battery should last at least 2 yrs, thats what I always thought. The batt lasts less than 2 years in this case for the 1.8l Grand Livina and I thought it should not be the case. A new maintenance free batt was installed for RM220 after RM10 trade-in for the old one.