The traditional way:
- Start with a circle.
- Extrude up on the Z axis.
- Scale.
- Extrude but don't move.
- Scale outward on not Z.
- Extrude on the Z axis.
- Scale inward on not Z.
- Extrude down on the Z axis.
- Extrude without moving
- Scale inward on not Z.
- Extrude down on the Z axis.
- Scale inward on Z.
- Extrude without moving
- Scale inward on not Z to almost closed.
- Select the original circle
- Extrude without moving
- Scale inward
- Shift select the inner upper cicle
- bridge edge loops.
(Do you think I remembered all the scale and extrude operations?)
Faster way:
- Add cylinder with no end caps.
- Position loop cut where you want straight part.
- Scale bottom to create taper.
- extrude bottom without moving.
- Scale inward to create water drain ring.
- Add Solidify modifier
