Here I will be comparing older Insurt screenshots to those from the final game. In the earlier screenshots, the basics worked, but there were numerous bugs with game logic and the UI hadn't been fleshed out yet.
Insurt level editor progression, WIP level editor (left) vs final version (right)
First, notice the older textures. These textures were completely WIP and show my amazing programmer art abilities. Some of these blocks changed significantly, such as the door & door activator blocks which went from orange to blue in order to increase contrast between the floor. The player cube is also 2d in the earlier screenshot.
Another thing to notice is the onscreen text. The earlier version uses Calibri while modern versions use Google's Roboto. The earlier version also did not have text shadow. It becomes clear that the UI was not complete by the use of default windows prompts, instead of the built in menu UI in the new version.
Insurt level select menu progression, old (left) vs new (right)
These screenshots demonstrate the importance of iconography in user interface design. Glancing at the old UI, it is quite difficult to tell which levels (if any) should be replayed to achieve a higher star count. Compare this to the new UI, where you can quickly glance and notice which levels are missing some stars. Even the back button is missing an icon in the older version. Overall, the newer menu design is easier to use and much nicer to look at.
Another thing to notice is the lack of a difficulty select in the older version. This feature had not yet been implemented.
Insurt pause menu progression, old (left) vs new (right)
Once again, the use if large icons makes the experience easier to use and more inviting for the player to interact with it. Icons make the game more universal, and easier to use for those who might not speak English.
Clearly, the new UI with icons and the newer textures make the game nicer and more user friendly.