According to a dictionary definition, musicianship is “knowledge, skill and artistic sensitivity in performing music”. These three factors are inseparable, and each builds successively upon one before, so we can’t ignore any of them if we want to be true musicians.
Knowledge alone does not suffice, since playing music also requires practiced movement to develop skill; skill does not suffice, since artistic sensitivity is essential for music to sound musical; and artistic sensitivity cannot be expressed without skill. But when all these factors are in place, we have good tone, smoothness, reasonable accuracy, confident playing, expression, dynamics, and the ability to learn well from whatever source is appropriate for the style of music we play (notation, tablature, by ear, etc.).
Many musicians believe that good musicianship primarily means being able to play a new piece of music at tempo and all the way through. There are certain situations in which one must play well at first sight-reading, but this skill is attained only after one has a good foundation in the other necessary skills. If the foundation is not there, its lack will be evident no matter how well you sight read or how quickly you think you’ve learned the piece. Learning a piece is so much more than just being able to play the notes at tempo. If you are striving foremost to get through a new piece so it sounds like you’re “playing music”, you’re barking up the wrong tree, because it always means sacrificing something such as fingering, technique, muscle memory, tone, and/or smoothness, but most importantly it often means sacrificing expression.
Expression comes after gaining a full understanding and experience of the music being played. Learning slowly, with focus, and with attention to detail and nuance, gives the player the ability to integrate a piece of music fully enough to then play it expressively. If you love music, why would you want to learn it any way other than completely?
Many musicians try to tackle pieces they aren’t ready for, perhaps because the pieces are beyond one’s current skill level, or because they assume some prior experience on another instrument will automatically translate to a new instrument. Intellectual understanding of how an instrument works and how the music is read does not translate to integrated skill!
In any case, not giving yourself enough time, with every new piece at any level, or as an actual beginner on a new instrument, rarely works well. Trying to “make it music” as quickly as possible sabotages the process of actual learning. The only way to achieve full musicianship is to be methodical and slow and purposeful and focused in practice until you know the piece inside and out. Then you will have both music and musicianship, rather than sacrificing the musicianship just to play the music.