Although the acceptable amount [of water for ritual washing of the hands before meals] is a fourth of a log, one should use abundant water in washing (Orach Chaim 158:10).
The Talmud states that Rabbi Chisda attributed his good fortune to his practice of using abundant water in the ritual washing.
Rabbi Yisroel of Salant was at an inn, and when he washed his hands for the meal, he was careful to use the minimum amount of water required. When his students wondered why he did not follow the recommendations of the Shulchan Aruch (Code of Law), Rabbi Yisroel replied, "Perhaps you did not notice that a servant fetched the water from a well. If I used water lavishly, it would be at her expense."
Many times the Shulchan Aruch states the letter of the law, then adds that it is commendable to go beyond it in stricter observance. However, such extra observance is only done for oneself. For instance, when rabbis are asked about the permissibility of any given practice, they must render their decision according to the letter of the law, but may add that stricter observance is commendable but not mandatory. Rabbis are not permitted to require from others more than the law dictates, even if their personal standards of observance are more demanding.