Especially true with bigger homes, improper roof pitch can result in the formation of flat spots where ever there are long stretches of gutter. When this happens remedy is not possible even by re pitching in one direction or another.
In most cases, the ideal solution is to simply install an additional downspout in the location where the problem is present. This will facilitate the draining of any accumulation of standing water. For rainwater to properly flow when entering into down spouts, it is essential for gutter pitch to be correct. The accepted standard pitch for the majority of gutters in use today should be approximately for about every 10 feet of gutter run, be a slope of about 1/4 inch.
If standing water is present in gutters that are otherwise clean following a rainstorm, then re-pitching is the best solution. Standing water is likely to result any time there is 1/4 inch of slope per 10 feet of gutter or less.
The best way to guarantee that gutters are properly draining is to inspect the gutter system using a ladder following a heavy rain. Improper sloping can be clearly identified anytime water is indeed pooling in the corners of the gutter system where there is no debris detected. The most effective remedy for this issue is to properly pitch the gutter section in question using a leveler.
In some cases, all that is required is to bend the hanger to produce adequate slope. If this is not possible, it may be necessary to remove sections of the gutter and then rehang it properly.
That said, working with a professional contractor or trained technician is always the best way to handle the problem. This is especially true if your system features seamless gutters.