Besides the scores of 30 and 70 - which may suggest potentially oversold and overbought market conditions - traders also make use of the to try and predict trend reversals or to spot levels. Such an approach is based on the so-called and divergences.
A is a condition where the price and the scores move in opposite directions. So, the score rises and creates higher lows while the price falls, creating lower lows. This is called a "bullish" divergence and indicates that the buying force is getting stronger despite the price downtrend.
In contrast, divergences may indicate that despite a rise in price, the market is losing momentum. Therefore, the score drops and creates lower highs while the asset price increases and creates higher highs.
Keep in mind, however, that divergences are not that reliable during strong market trends. This means that a strong downtrend may present many divergences before the actual bottom is finally reached. Because of that, divergences are better suited for less volatile markets (with sideways movements or subtle trends).