A concave lens never changes its mind — the image is always virtual, erect, and smaller than the object, wherever you place the object.
Wherever the object is, the concave lens gives a virtual, erect, diminished image on the same side as the object.
A concave lens is refreshingly simple compared to a convex lens: no matter where you place the object, the image is always virtual, erect, and diminished, and it always forms on the same side of the lens as the object, between the optical centre and the near focus.
As the object moves from infinity toward the lens, the image shrinks along with it, moving from the focus toward the optical centre — but it never flips to being real or inverted, and it never magnifies. This predictable diverging behaviour is exactly why concave lenses are used to correct myopia (short-sightedness).
Key exam points
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Image Formation by Concave Lens — Chapter 10, Light, NCERT Class 10 · NCERT Science