The last thought at the time of death is most important. It is the fruit of all the thoughts and attachments of your time on earth. If one wants to be with divine, then one must cultivate onepointed fixation on divine throughout their life, above all other preoccupations, otherwise one will not be strong enough to conquer other distractions in the final moment. What one places most attention /awareness, intensity of emotional charge on throughout life until the very end is the fruit of your journey.
One may fall asleep today and not wake up tomorrow. It’s as simple as that.