In this presentation I will address the so-called Delta I=1/2 problem in the K -> pi pi weak decays together with some strategies for its understanding. 
The hierarchy of the I=0 and I=2 transition amplitudes remains unknown and only recently, direct determinations on the lattice have been attempted with large error bars. 
Moreover, even though the large Nc limit predicts no hierarchy, phenomenological approximations often invoke large Nc inspired approximations. 
Therefore, the Nc scaling as well as the charm mass dependence, both on the lattice, can help understand the origin of the Delta I=1/2. 
I will present the first results on the Nc dependence of the K -> pi pi amplitudes, that can be related to K -> pi pi through chiral perturbation theory (https://arxiv.org/abs/1607.03262).