By default, the prices shown on the Bybit chart are the price history and movement of the platform's Last Traded Price (LTP). On the other hand, liquidation is triggered by the Mark Price (yellow price figure on the order book) but not the LTP (the price you see on the LTP charts, price figure on the left of the order book) due to the adoption of Bybit's Dual-Price Mechanism. The liquidation engine will take over the liquidation process of your position only when the Mark price reaches the liquidation price of your position. 

As such, if a trader sets their Stop Loss to be triggered by LTP or index price very close to the liquidation price, it is possible for the Mark Price to hit their liquidation price first before the LTP/index price could trigger his stop loss. For example, Trader A holds a Buy Long position with a liquidation price of 12,000 USDT and they set a Stop Loss at 12,030 USDT with LTP as the trigger price. If the Mark Price has already reached 12,000 USDT while the LTP is still at 12,050 USDT, then the liquidation is triggered.

Ideally, the price of the Perpetual Contract (Last Traded Price) follows the Spot price of the underlying asset. However, this is not always the case, as Perpetual Contracts have their own demand and supply dynamics, which often lead to differences in the LTP and the Mark Price.

You can view the Mark Price history on the price chart in two (2) following ways:

Step 1: Enable the Mark indicator at the bottom of the chart. Select the time interval of the Last Traded Price chart to 1 minute for more detailed Mark Price changes.
 

Step 2: If you want the Mark Price last value label to be displayed on the chart, go to Chart Settings and check the Mark Price box under the Chart Display.
 

Step 3: Go to Chart Settings → Others to configure the Mark Price settings to High (for a short position) or Low (for a long position).