Valuation is the heart of investing and close to irrelevant for short-term trading. Both things are true, and knowing exactly where the line falls saves you from two opposite mistakes.
What a multiple actually is
P/E — price divided by earnings per share. A P/E of 25 means you are paying 25 rupees for each rupee of annual profit.
The crucial reframe: a multiple is not a measure of value. It is a measure of expectation.
A high P/E does not mean expensive. It means the market expects earnings to grow. A low P/E does not mean cheap — it often means the market expects earnings to fall.
That single reframe explains most of what confuses beginners about valuation.
The main multiples, briefly
| Multiple | What it compares | Most useful for |
|---|---|---|
| P/E | Price to profit | Profitable, stable businesses |
| P/B | Price to book value | Banks and financials |
| EV/EBITDA | Enterprise value to operating earnings | Comparing across different debt levels |
| P/S | Price to sales | Businesses not yet profitable |
P/E is the default and the most misused. It breaks down entirely for loss-making companies, is distorted by one-off gains, and is not comparable across sectors — an IT company and a bank have structurally different normal ranges.
Why cheap stocks keep falling
The most expensive lesson in valuation, and it has a clean explanation.
A low multiple usually exists for a reason. Earnings are expected to decline, the business faces structural pressure, the accounts are not trusted, or governance is questionable. The market has priced what it knows.
Buying purely because a multiple is low is betting the market is wrong about a widely-known company. Sometimes it is. Usually it is not, and "cheap" simply gets cheaper as the reason plays out.
A low multiple is a question, not an answer. The question is: why is it low? If you cannot answer that, you do not have a thesis.
The cyclical inversion
This catches people who have learned the basics but not the exception.
For cyclical businesses — commodities, metals, autos — the multiple works backwards.
At the peak of a cycle, earnings are at a maximum, so the P/E looks lowest — exactly when the stock is most dangerous. At the trough, earnings collapse and the P/E looks enormous or meaningless — often the best time to buy.
So for cyclicals, a low P/E is a warning and a high one can be an opportunity. Applying the normal rule inverts the correct conclusion.
Where this matters to a derivatives trader
Honestly: less than the rest of this track, and it is worth being clear about that rather than pretending otherwise.
Valuation is a poor timing tool. "Overvalued" is not a sell signal and has bankrupted people who treated it as one. Markets stay mispriced far longer than any option lasts.
Three places it genuinely helps:
Understanding volatility around results. A stock priced for high growth has further to fall if it disappoints. High multiples mean higher event risk, which is directly relevant to sizing and to whether you hold through results.
Explaining sector behaviour. When a whole sector re-rates, valuation is usually the reason. Understanding why something is happening is legitimate even when it does not generate a trade.
Avoiding fragile instruments. Extremely stretched valuations plus heavy debt is a combination that gaps. That connects directly to the gap-risk lesson.
The five-minute version
For a derivatives trader, this is the whole workflow:
- Is the multiple extreme relative to this company's own history?
- If low: why? If you cannot answer, treat it as a warning rather than an opportunity.
- If high: expect larger moves on disappointment, and size accordingly around results.
- Is it cyclical? If so, invert your reading of the multiple.
Anything beyond that belongs to investing, which is a different activity with a different horizon and a different set of tools.
Check yourself
0 of 4 answered1.A company trades at a P/E of 45. What does this most directly tell you?
2.A cyclical steel producer shows its lowest P/E in a decade. What does this most likely indicate?
3.Why is a low P/E described as 'a question, not an answer'?
4.Where does valuation genuinely help a short-term derivatives trader?
What to take away
- A multiple measures expectation, not value. High P/E = expected growth, not "expensive".
- Compare within a sector and against the company's own history. Cross-sector comparison is meaningless.
- A low multiple is a question: why is it low? No answer means no thesis.
- For cyclicals the multiple inverts — low P/E at the peak, high at the trough.
- Valuation is a poor timing tool. Never build an option thesis on it.
- It genuinely helps with event risk sizing and avoiding fragile instruments.