The screen price is not an exit guarantee
An order book may show a last traded price of PHP 100. If only a small amount is available near PHP 100, selling a large position can consume bids at PHP 99.80, PHP 99.50, PHP 99 and lower. The average exit can therefore be materially below the headline price.
The spread tells you the gap between best bid and ask. Depth tells you how much size is available at successive prices. Slippage is the difference between the price assumed and the price actually obtained.
A simple depth example
Suppose a learner wants to sell 1,000 units. The fictional bids are:
| Bid | Quantity |
|---|---|
| PHP 100.00 | 200 |
| PHP 99.80 | 300 |
| PHP 99.40 | 500 |
Selling all 1,000 units into these bids produces an average price of:
(200×100 + 300×99.8 + 500×99.4) ÷ 1,000 = PHP 99.64
The last displayed price may have been PHP 100, but the executable average for the full size is PHP 99.64 before fees.
Headline volume can mislead
Twenty-four-hour volume does not tell you how much can be sold right now at acceptable prices. Volume can be distributed across venues, concentrated in other trading pairs or inflated by activity that does not represent durable depth.
For exit risk, the useful question is closer to: how much can be executed within my acceptable slippage under normal and stressed conditions?
Stress can make liquidity disappear when it is needed most
During a sharp market move, market makers may widen spreads or withdraw quotes. An exchange can also become unavailable. Therefore the liquidity observed before entry should be stress-tested rather than treated as permanent.
No-money practice
Create a fictional order book with five bid levels and calculate the average price for selling 100, 500 and 1,000 units. Then halve the depth and widen the spread to simulate stress. Compare the resulting slippage.
*Cryptocurrency and virtual asset transactions are highly volatile and irreversible, may result in significant losses, and do not guarantee returns; customers should trade only after understanding the risks involved.
