Is it obligatory for someone who follows one of the four schools of thought in Wudu’ (ablution) to adhere to everything that school states regarding the pillars and nullifiers of Wudu’, or is it permissible for him to selectively adopt what suits him from each school of thought?

A Muslim should emulate the Prophet, peace and blessings be upon him, in his ablution and all other acts of worship. There is no harm for a common person to follow one of the established madhhabs (schools of thought). The conclusion is that composite taqleed (following different madhhabs for different parts of the same act of worship), such as someone who performs ablution and wipes a few strands of hair on his head, imitating the Shafi'i madhhab (definition), then touches his private parts with his hand, imitating the Hanafi madhhab, is not permissible according to many scholars. This is the more cautious approach, especially if the purpose is to seek out dispensations. Some scholars have permitted this type of composite taqleed, but it is safer to avoid it. However, this entails difficulty and hardship for common people. The correct view is the permissibility of composite taqleed, not with the intention of seeking out dispensations, but when it occurs incidentally, especially for common people who have no other alternative.