Accelerated Development

Summary

 * Accelerated Development is the ability to increase a character's skills, statistics and/or abilities faster and more effectively than what a normal character in that setting is able to. Thus, users of this ability are able to improve upon their natural abilities, as well as the ones that they are trying to learn at an accelerated pace. A technique that would take a normal person years to learn and master can be mastered by that person within weeks, days, or even immediately upon seeing it the first time.
 * A character with this particular ability can strengthen their abilities to the point that he/she can even be considered beyond the limitations of even other members of their own species, whether the cause of that character's accelerated development is due to their genetics, or artificial enhancements that were granted by external influences.

Possible Uses/Cases

 * Physically, the user's strength, speed, durability, and stamina can grow at an accelerated pace, allowing them to dish out more damage, move faster, endure stronger attacks, as well as last longer in a fight condition. Increases in this area allow the body to adapt to the user's accelerated growth, thus the chances of this character seriously injuring themselves via over-exertion of their physical capabilities are rare.
 * Mentally, the user's mind/mental capabilities are able to advance to the point that their intelligence far eclipses that of a normal human, or their learning capabilities increase to the point that they can learn things at a much faster rate in comparison to others. An advanced version of this ability fits in under:
 * Instant Learning: Where a user is immediately understand anything they see or hear about, whether by seeing/practicing it for a short period of time.
 * Intuitive Aptitude: Where a user is able to instantly grasp the inner workings and mechanics of different objects, where these objects can range from things that are simple to those are extremely complex in nature. Users of this ability are also able to understand things (events, objects, subject, abilities, etc.) on an intuitive level without the need of an explanation, or long periods of study on their end.
 * Ability-wise, the user is able to master an ability/technique much faster in comparison to the time it takes for others to master it.

Limitations

 * The user still requires a certain amount of time for their skills to develop.
 * At a certain point in progress, the user may require assistance if they are to develop further.
 * The number of abilities that can be developed further can be limited, usually only limited to one area of expertise.
 * The user may need to continuously train this particular ability in order to maintain progress/capability.

Users
A whole bunch of characters could fit for this trope, actually.
 * Characters from Dragon Ball, especially the Saiyans (Dragon Ball series)
 * Naruto Uzumaki (Naruto): Shadow Clones multiply the rate of Naruto's learning capability depending on the number of Shadow Clones produced.
 * Tatsumi (Akame Ga Kill): Esdeath notes that Tatsumi has immense potential; his combat skills/abilities increased drastically in comparison to others throughout the series.
 * Shin/Li Xin (Kingdom)