What works today, might not work tomorrow

What works today, might not work tomorrow, next week or next year. This is applicable to flies, bead colors, hot spots, size of flies. And remember, fish do have a memory, they do remember flies that have pricked them if you practice catch and release (Which you should be doing). So change and adapt to keep on catching fish. If you fish the same water, week in and week out, try different flies, different techniques (dry fly one week, nymphs the next week, wet flies the following week, streamers the week there after and soft hackles the last week.)
You can use all the mentioned techniques in either an upstream or downstream style. Your technique will change, the style and the presentation - plus you will become a better all round fisherman.