1. Relying on AUTO mode
Using manual mode will make SUCH a huge difference in the overall look & feel of your photos, and cut back on editing time too.
2. Poor/inconsistent lighting
You may not have fancy studio lighting, but that is OK! Finding ample natural light indoors or even going outside can help immensely. Also considering using a bounce board for more even coverage.
3. Focus problems
Use focus points on your camera or tether to a computer so that you can zoom in to make sure that everything is crisp and clear. If working on a flatlay, consider a higher f-stop so that items of different heights can remain in focus.
4. Camera movement during stop-motions
Make sure to use a tripod (or better yet, a c-stand), and try not to touch the camera for any reason. Tethering to a computer or utilizing a remote shutter can also help eliminate camera shake.
5. Not leaving enough negative space
Aside from helping to achieve a cleaner look, negative space can also help when trying to crop to different aspect ratios.
6. Inconsistent color palette
Each photoshoot should have a consistent and cohesive color palette that aligns with the brand/goals. This includes backgrounds as well as props!
7. Glare
Nothing ruins a photo more than a streak of glare across a product label or certain props. Change your angles and move your light source until you can find a way to make it disappear!