kaizen - noun
Continuous and incremental improvement.

Originally a Japanese term roughly meaning "change for better", kaizen has been adopted as a principle for improving manufacturing efficiency, business practices, and life in general.  The concept of kaizen is useful for approaching general improvement processe, including one's training.  Progress rarely occurs in large steps.  Scientific knowledge advances step by step.  Strength skills improve gradually over the course of weeks to months.  Writers usually craft their works over extended periods of time rather than banging out something in a single sitting.  While leaps in progress do occur, forward progress mostly happens in small, continuous increments.

One frustrating thing in my own training is remembering that the improvement process is normally gradual rather than sudden.  Jumps in my understanding happen from time to time, but for the most part, it's slow and steady progress towards improvement.  This has become particularly true recently as I find myself with fewer and fewer large blocks of time to just practice.  Improvements come slower without the blocks of practice time.  Life's many challenges may slow down my training, but daily practice (no matter how short) means I make some sort of progress every day.  Each day, I practice kaizen and take another small step forward towards improved understanding.