Well, obviously. Many games are infamously abandoned at the "little dude running around a mostly empty map" stage... but without that first stage you'll never have the motivation to go on. And even abandoned prototypes can be mined for ideas, mechanics or code later. At worst, they're a learning experience. Besides, if it's not fun for you to simply work on games, why even bother.
I think you have to take joy in the little things, progress is progress and nobody starts out knowing everything, at that point there will inevitably be more lows than highs, 2 examples from when i first started, 1 - Trying to make a hookshot for my Zelda game and accidentally creating infinite loops and wondering what the hell was happening and why it kept crashing (seems stupid doing this looking back but i was a beginner). 2 - Creating the mini map engine for the same game (this took me weeks if not months of testing to figure out and to this day the only bit of code i wrote down on pen and paper should the worst happen, which thank christ i did because it did). These were majorly frustrating at the time but the joy i had when i figured out where i was going wrong was immeasurable.