Taqleed is based on the logical necessity for the non expert to refer to the expert.
This is followed in every field of knowledge in life. All human beings practically follow this fact in every matter. Religious day to day rules are not an exception. Non experts in religious studies need to follow the experts. We believe that every religious act must be based on real evidence. Evidence is known to the experts who spend long time in studying and researching the Islamic sources ( Quran, Hadeeth, Aql and Ejmaa'). People must refer in religious matters to the most learned Islamic scholar who is called al-'Alam.
From the time of the Prophet (SAWA) and the Ifallible Imams, Muslims who lived in places far away from them, were ordered to refer in religious matters to the scholar in their area.
Taqleed is obligatory on non experts in religious studies (non Mujahid or non Muhtaat). With out Taqleed, non expert will practice religious acts with out authentic evidence and this is not accepted in Islam.