In other situations, like when you enter your stock position at a very low price point because the stock is new or the company is untested, it's easy to experience spiffy-drops on the regular. If your investment was $5, for example, and the company has since proven itself and its stock shares are now over $200, a spiffy-drop of 2.5% isn't great, but it's also not world-ending.
When spiffy-drops are signs of bigger problems, there are times when you probably should have already noticed something was going wrong long ago. A stock that's slipping isn't spiffy-dropping yet; it's simply losing value. If it's been doing this for a while, it's also probably losing investor faith, and that's likely to result in spiffy-drops for a wide swath of investors.
What you want to do is stay ahead of the market sentiment train if there's truly a reason the pricing is dropping, and it's not just because of the whims of the marketplace. If it's due to a real concern about the fundamentals of the business, you may not want to stick it out long enough for problems to be corrected (if they can be) so your investment can continue to grow.