Mesorah and Machlokes
Question
How is there Machlokesim in Halacha if we can just go back two generations to find out the answer?
Examples:
Rashi vs Rabbeinu Tam Tefillin, Just find out what people wore 100 years before
Beis Hillel vs Beis Shammai Vis a Vis lighting menorah, or Yaknahaz on Yom Tov what did they do before Hillel and Shammai
Thank you in advance for your reply and have a Good Shabbos