As a beginner...I think its most important to intentionally NOT finish tracks. Most people will disagree with me but its mostly what I have experienced and seen myself as a beginner.
For example...take me for instance. I have only been producing/making beats for 2 years now approximately. I have yet to finish a track. I mostly just have 4-8 bar loops of beats, synth leads, basses, chords and one shot type stuff that I have finished myself. I don't try and tell myself to finish a track.
My theory is...If you occupy yourself with trying to finish tracks and you haven't yet mastered the 'basics/foundation work' that is crucial...Than it can ultimately lead you to frustration, hurt and anger. Of which would ultimately kill your creativity and the FUN. Therefore...ruining your production dream/career all together.
Because I am not focused on finishing a track...I mainly focus on the basics/foundation work of music production...Like sound design, music theory, making strong/good melodies and chords, focusing on mixing techniques, training my ear for sounds that go together well and creating an efficient workflow that suits me.
Honestly...I just try to have FUN and not worry so much about finishing a track. Music production should be FUN. Case in point...I also snowboard as another hobby to past time and what not. In snowboarding culture...we have a saying..."the best snowboarder, is the one that's having the most FUN". And I think that theory/mentality is also the same for music production and the music/producer culture. I have heard numerous stories that say some of the world's best producers/bands/DJs/artists best songs/works...were mostly a result of them having FUN and not focusing on other aspects (such as a time restraint).
So...My advice is...don't worry about finishing a track. Just focus on having FUN, being creative and making mistakes. Finishing a track will come in due time...when ever that is. Don't limit your creativity/FUN by telling yourself you need to complete something.
My 2 cents.