Why does a trading app become slow during market volatility?

During high volatility, the sheer volume of orders, price updates, and data requests hitting the exchange and the broker’s servers spikes dramatically compared to a normal trading session, and this surge can strain both the broker’s backend infrastructure and your own device’s ability to render rapidly updating data smoothly. Market open, major news events, and circuit-hitting moves are exactly when this tends to happen, since that’s when trading activity and data volume peak simultaneously across potentially millions of users on a popular platform. This isn’t unique to any one broker; even well-built platforms can show some lag during extreme volume spikes, since the infrastructure needed to handle peak-moment load at scale is a genuinely hard engineering problem. If the app becomes slow or unresponsive during a critical moment, like when you need to exit a position, you switch to the web terminal or, as a last resort, call the broker’s dealing desk, rather than repeatedly tapping the same button and risking a duplicate order once the app catches up.