What other definitions for a planet were proposed? This article from the IAU states

The first draft proposal for the definition of a planet was debated vigorously by astronomers at the 2006 IAU General Assembly in Prague and a new version slowly took shape. This new version was more acceptable to the majority

What were the other proposals for the definition of a planet? What was changed between the first draft and the final version that was voted on?
The IAU website has this draft definition of &quot;planet&quot; and &quot;plutons&quot; page, published on 16 August 2006 in Prague. It says (emphasis mine):

The world's astronomers, under the auspices of the International
Astronomical Union (IAU), have concluded two years of work defining
the difference between &quot;planets&quot; and the smaller &quot;solar system bodies&quot;
such as comets and asteroids. If the definition is approved by the
astronomers gathered 14-25 August 2006 at the IAU General Assembly in
Prague, our Solar System will include 12 planets, with more to come:
eight classical planets that dominate the system, three planets in a
new and growing category of &quot;plutons&quot; - Pluto-like objects - and
Ceres. Pluto remains a planet and is the prototype for the new
category of &quot;plutons.&quot;

The proposed 12 planets Solar System looked like this (credit: The International Astronomical Union/Martin Kornmesser):

The final press release, published on 24 August 2006, says:

The IAU members gathered at the 2006 General Assembly agreed that a
&quot;planet&quot; is defined as a celestial body that (a) is in orbit around
the Sun, (b) has sufficient mass for its self-gravity to overcome
rigid body forces so that it assumes a hydrostatic equilibrium (nearly
round) shape, and (c) has cleared the neighbourhood around its orbit.
This means that the Solar System consists of eight &quot;planets&quot; Mercury,
Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. A new
distinct class of objects called &quot;dwarf planets&quot; was also decided. It
was agreed that &quot;planets&quot; and &quot;dwarf planets&quot; are two distinct classes
of objects. The first members of the &quot;dwarf planet&quot; category are
Ceres, Pluto and 2003 UB313 (temporary name).

Which looked like this (credit: The International Astronomical Union/Martin Kornmesser):

So in 8 days, the IAU switched from a 12 planets system, with a planet subcategory called &quot;plutons&quot;, to a 8 planets system, with an dwarf planet category distinct from the planet category. How did that happen? It's probably something only a General Assembly attendant who witnessed the discussion would know. It must have been quite a debate!