Bollinger bands are very popular in TA. Upper band acts as resistance and lower band acts as support. Look at Wilmar's daily chart, we see that price has pushed past the lower band. This gives us a very bearish picture. Support is weak. It also tells us that the counter is deeply oversold but remember that in very bearish conditions, oversold can stay oversold. It really doesn't say anything else.
Conventional TA tells us that we should buy when price breaks the lower band. This is to take advantage of oversold conditions. The belief is that, eventually, price would return to the lower band and then the middle band. The operative word here is "eventually". When exactly? Your guess is as good as mine, is it not?
Anyone who bought Wilmar's shares three sessions ago as it closed below the lower band at $4.70 would be licking ......