CC3220SF-LAUNCHXL: PRCMSysResetCauseGet() clarification

Here I noticed a non-intuitive behavior (I hope explained somewhere) about the return value of PRCMSysResetCauseGet() when debugging (i.e. when launch the firmware using XDS and with __SF_DEBUG__ defined).
On our boards I see the same bahavior even when burning an image with UniFlash with __SF_DEBUG__ NOT defined.

Example:

void ApplicationTask(void)
{
    InitSimplelink(ROLE_STA);

    UART_PRINT("[SYS] Reset cause is ");
    _u32 resetCause = PRCMSysResetCauseGet();
    _u32 wakeCause;

    switch (resetCause)
    {
    case PRCM_POWER_ON:
        UART_PRINT(0, "power on\r\n");
        // do something
        break;

    case PRCM_LPDS_EXIT:
    case PRCM_CORE_RESET:
    case PRCM_MCU_RESET:
    case PRCM_WDT_RESET:
    case PRCM_SOC_RESET:
    case PRCM_HIB_EXIT:
        wakeCause = PRCMHibernateWakeupCauseGet();
        UART_PRINT("Sysreset = %lu\tWakeup = %lu\r\n", resetCause, wakeCause);
        // do something else
        break;
    }

    // ....
}

The very first time I burn the image I get the value 0 for PRCMSysResetCauseGet() which is PRCM_POWER_ON. Then my firmware will put the MCU in hibernation state. No way to get another PRCM_POWER_ON even removing the batteries for minutes (shorting the VBAT to discharge any capacitor). It always returns PRCM_HIB_EXIT.

The only way I found to get another PRCM_POWER_ON is:

1. connect the XDS to my board
2. remove the batteries from my board
3. reset the XDS (I'm using the launchpad, so I press the push-button close to USB connector)
4. insert again the batteries: now it shows power on

What am I missing here?

SWRU465 at page 501 says:

unsigned long PRCMSysResetCauseGet(void)

Description: This function acquires the reason for an MCU reset. This is a sticky status.
Parameter: None
Return: Returns the MCU reset cause as one of the following:
• PRCM_POWER_ON: Power-on reset
• PRCM_LPDS_EXIT: Exiting from LPDS
• PRCM_CORE_RESET: Software reset (core only)
• PRCM_MCU_RESET: Software reset (core and associated peripherals)
• PRCM_WDT_RESET: Watchdog reset
• PRCM_SOC_RESET: Software SOC reset
• PRCM_HIB_EXIT: Exiting from hibernate

What does "this is a sticky status" mean?