When a funnel appears by your cursor, it indicates that one or more selection filters are turned on.  If you close the file and reopen it, the filters are cleared but they serve a very useful purpose and can easily be turned on and off.

What is a selection filter?  It’s a tool that helps pick what you want by only selecting those things that are filtered.  There are many items that can be filtered.  Here they are displayed on the Selection Filter toolbar:

To access this toolbar, right-click on one of the tabs in the Command Manager and go to the Toolbars flyout.  When it’s turned on, it appears on the screen where it was last positioned, the default location being docked in the lower left corner.

One or more filters can be turned on at the same time.  Three of these filters have pre-defined keyboard shortcuts assigned to them; V filters vertices, E filters edges and X filters faces.

This is why we sometimes see the funnel by the cursor without intentionally turning on any filters.  We inadvertently hit the E, V, or X key.

If you’re not sure which ones are on and you want to clear them out, F5 is a pre-defined keyboard shortcut that toggles the selection filter toolbar on and off, enabling you to see which ones are on and clear them.

The one I personally find most useful is face filters (X on, X off).  When face filters are turned on, SOLIDWORKS will only pick faces.  This can be useful in any part or assembly where small faces need to be selected.  I find it especially useful in assemblies when mating parts.  More often than not it’s faces that get selected.  The filters can be turned on and off as needed, even when a command is active.