UV maps names shouldn't be included in the material
Many people rename the UV maps and this means the materials won't work for them out of the box.
Quite often including such names also generates black thumbnails from the automatic thumbnailer in the add-on.
You can simply delete the UV map names from the material and regenerate the thumbnails.
See next articles
Low range HDRs aren't HDRs
Images that have 8bit depth or their values are capped between 0 and 1 aren't real HDRs
Material bump intensity shouldn't be too strong
If you overdo bump intensity in Blender, you can get not only unrealistic look, but also shading artefacts.
DirectX normal map
Your normal maps don't match the OpenGL standard. The material will not look correct after being downloaded from the BlenderKit.
The nodes are organized in a confusing manner. This may cause inconvenience to BlenderKit users.
material Subsurface scattering radius
Subdivision surface scattering radius in Blender is in metric units and should rarely be over 0.05
Wood mapping on model
The wood should always be mapped with the grain oriented parallel to the longer side of the wooden part, then the material in the BlenderKit database will look great.
Plant leaves with the alpha channel overlapping
Leaves with the alpha channel overlap, this can lead to an unrealistic rendering of the plant.
Model Topology Issues
There are topology issues in this model, like double/overlapping faces, double vertices, non-manifold faces, subdivision surface artifacts, or similar.
Wrong meshes or missing parts
Some parts seem to be missing, for BlenderKit uploads, be sure everything is parented to a single parent and not to include (unparent) any extra hidden meshes.
Missing textures in file
If filepaths to the textures are complex or have non-standard characters, Blender might have problem packing these.
Improve materials on Model
There are some things to improve in your materials. Please study how to correctly use Cycles / EEVEE material systems to reach a better result.
Why applying scale (and rotation) matters
So many reasons to apply scale whenever you can in Blender 3D!
Model unrealistic shape
The shape/proportions of the of the object aren't realistic. Check reference pictures to study more the real shape of this object.
Put the model on the ground
The model in the scene should lie in a natural way for faster production and to follow the drag & drop philosophy of BlenderKit database.
In this short article, we will talk about Fantasy Design. As a rule, novice designers do not have enough knowledge, but they have a great desire to do Fantasy Design.
Texel density in Blender
In this article we will talk about what texel density is and its proper understanding from the point of view of the BlenderKit team
How to add translucency to the leaves in Blender
In this short video tutorial, I will explain how to add translucency to leaves.