Many people regard Yahrtzeit customs and observances with much reverence and importance. The psychological reasons for this are self-evident, as such observances provide people with a feeling of connection to their deceased relatives and loved ones.
Is there any halachic basis for the importance accorded to Yahrtzeit observances, other than the psychological aspect of it? For example, if one derives no psychological satisfaction from Yahrtzeit observances, is there any halachic reason for him to perform them anyway?