Why can't I create a Sketch Point at the same location as an existing point?
When a line's endpoint is drawn sufficiently close to another line in the same sketch - it performs a Merge (see above). When the endpoint is drawn within snapping distance of a model vertex, it captures a Coincident relation. The only exception is in the placement of a Sketch Point [Tools - Sketch Entities - Point], which you cannot place on the endpoint of a line or arc. This is prevented because the Merge relation would cause the Sketch Point to dissolve into nothing. However, for the Hole Wizard and Sketch-Driven Pattern and other situations with laying out construction sketches, the user sometimes wishes to put a Sketch Point on top of an existing endpoint.
There are actually two easy ways to place sketch points on the end of some other sketch entity:
1) Although you cannot snap a Point onto the end of a Line, you can perform the reverse. Sketch the Point first, then snap the Line over it.
2) Alternately, you can place the Sketch Point graphically near the desired endpoint, and then create a Coincident relation.
