Why are there several house systems and could they all show a part of us?

The 2 house systems change the sign and planet for a few of my houses, but it seems like both are correct in some way....like my 3RD HOUSE in Libra, or Scorpio, both make sense because l moved around so much, my neighborhood could be said to be my home. So they alternate.

Here's the distinction between equal house and placidus :

The several methods of calculating house divisions stem from disagreement over what they mean mathematically (regarding space and time). All house systems in Western astrology use twelve houses projected on the ecliptic. The differences arise from which fundamental plane is the object of the initial division and whether the divisions represent units of time, or degrees of distance.

If SPACE is the basis for house division, the chosen plane is divided into equal arcs of 30° each. A difference will be made as to whether these divisions are made directly on the ecliptic, or on the celestial equator or some other great circle, before being projected on the ecliptic.

If TIME is the basis for house division, a difference must be made for whether the houses are based on invariant equal hours (each house represents 2 hours of the sun's apparent movement each day) or temporal hours (daytime and night-time divided into six equal parts, but here the temporal hours will vary according to season and latitude.)

Regardless of these different methods, all house divisions in Western astrology share certain things in common: the twelve house cusps are always projected on the ecliptic; they will all place the cusp of the first house near the eastern horizon and every house cusp is 180° of longitude apart from the sixth following house (1st opposes 7th; 2nd opposes 8th and so on).[4]