The cycle repeats, producing a square wave. The frequency is determined entirely by the RC time constant and the specific threshold voltages of the 74HC14.
When power is applied, the capacitor is empty (0V). The Schmitt trigger sees a "Low" input and outputs "High" (~5V). 74hc14 oscillator calculator
: As the voltage drops, the gatekeeper again waits. It won't flip back to High until the voltage falls all the way down to the Lower Threshold Voltage cap V sub cap L minus end-sub ), typically around The cycle repeats, producing a square wave