A change in long term momentum can forecast that the trend is near the end!
Energy is required to move a stock, and YES it does run out! Energy (demand or supply) can be measured by standard momentum tools (Detrending Price Osc), and keeping an eye on the longer term momentum trend is vital to keeping your profits.
Wyckoff traders must monitor long term momentum to check accumulation and distribution patterns on there charts. Major price weakness will be forecast by major momentum weakness.
Below are two major trend changes.
"Success in trading means excess of profits over losses. If anyone tells you they can almost be invariably successful, put him down as trying to impose on your credulity." ~ Richard D Wyckoff
"The stock market is filled with individuals who know the price of everything, but the value of nothing." ~ Philip Fisher
"In the short run, the market is a voting machine, but in the long run it is a weighing machine." ~ Benjamin Graham
"Successful speculation requires staying on top of changes in industries and companies that either create new industries or improve on existing industries. The majority of your profits will come from these two ... The shrewdest traders throughout history all adapted the skill of reactionary change, as the market constantly presents new and different opportunities." ~ Bernard Baruch
"Markets are constantly in a state of uncertainty and flux and money is made by discounting the obvious and betting on the unexpected." ~ George Soros