Glance at the photo above. See anything that may be wrong?
It appears this is a pistol. Notice the muzzle and what I think is the recoil spring guide to the left in the frame. If I am right, the photo depicts a non-recommended way to clean almost every barrel.
The preferred and appropriate way to clean your gun’s chamber and bore is to “push” your cleaning patch, brush, or jag from the chamber and “push” towards the muzzle, just like a bullet travels. In pistols, this normally means removing the barrel from the frame and start your patch, brush, or jag from the chamber. With rifles, the same rule applies. You may need to remove the bolt to be able to push a rod straight through the bore. “Pushing” helps reduce the risk of nicking your barrel crown.
In addition, you can insert the rod starting at the muzzle, pass it through the bore and chamber, attach your brush or patch, and “pull” it back through the bore. The patch or brush still will be traveling as the bullet travels. Of course, multiple passes will require you remove and then re-attach patch or brush each time.
An exception are revolvers, of course. In most cases, you must start from the muzzle since access to the other end of the barrel is not possible with a standard cleaning. Something like a bore snake or a bush that is on a flexible rod (such as is shipped with many new pistols) may give you the option to clean from the back towards the muzzle.
Be safe and shoot straight!