I remebered hearing the story about Rav Ketina and why to wear tzitzis it is discussed on many websites after i did a google search for Rav Ketina’s name
the Gemara tells of a certain Rav Ketina who purposely wore garments that did not require tzitzit on them. He encountered an angel who told him that he was not doing the proper thing. Indeed, the angel told him that although one who does not wear a garment with tzitzit has technically not transgressed the mitzvah and therefore, is not punished directly; nevertheless, when Heavenly Wrath is forthcoming he becomes more vulnerable to it, as he is lacking the extra protection that the mitzvah of tzitzit would afford. The second Gemara relates that one who is conscientious in performing the mitzvah of tzitzit will receive the great reward of being able to greet the countenance of the Divine Presence at the end of his days.
An excellent downloadable to word presentation from virtual bais medrash to the extent of obligation