Part year NI contributions do not count as a qualifying year. This discriminates against those who do not have a continuous record of being in paid employment. In particular, this is likely to indirectly affect women.
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It is quite possible for individuals to have a high number of incomplete qualifying years, especially where someone has worked part time or been economically inactive, but none of this would currently count towards qualification for a full state pension.
As the minimum number of qualifying years to receive a full state pension is now 35 years, the current law contributes to keeping people in poverty in retirement. This law therefore needs to be changed.