Lane Assistant (PLGA) based on human editing? — Errors!

I've been noticing that MapFactor Navigator's PLGA (passive lane guidance assistant, on Android) can't be trusted because it makes various mistake types:

• mt1: the arrows show confusing/incoherent information or simply wrong information!
• mt2: the arrows don't show up at all, while other gps navi apps (like TT Go Mobile or Navigon) do show the LGA at that critical street crossing!
• mt3: the arrows don't look at what's ahead, e.g. showing 2 green arrows instead of 1 green arrow!
  

I've encountered such PLGA mistakes in the MFN app often enough, and it would be a full-time job to make a list of all these examples ("debug the extensive code/database") i've come across. It is not my job to find, document, list, and fix all the instances where the PLGA makes mistakes. The bottom line is that i am beginning to lose trust in
the software. But i've been wondering from where these PLGA mistakes originate, why the PLGA makes mistakes.

Question:

Is the PLGA 100.0% dependent on the OpenStreetMap (OSM) data AND is the PLGA 100% automatically generated by the software, exclusively and directly based on the OSM data? OR has the PLGA been manually edited by MF programmers, i.e. added, checked, tested, edited?

Maybe the PLGA
does lane guidance errors because of wrong OSM data, OR
because of human error by MF programmers. I would like to know! Well, if the former is the case,
then the PLGA should make less mistakes with TomTomMap (TTM)
data, because all
my tests with TomTom software didn't show any PLGA mistakes: i can
totally trust the TomTom GO Mobile app! So I've been wondering if the PLGA based on TTM
data shows similar mistakes induced by MF editors.

I don't want to
spend 15 or 20EUR, only to find out that i am not gaining a clear
advantage over the FREE OSM data. If i learn that the PLGA w/ TTM data
has the identical behavior as TomTom's PLGA in the TomTom GO Mobile app,
then i would be certainly interested in buying the TTM for MFN. The gain of spending 20EUR for TTM data would be the faultlessness of MFN's PLGA then!

Side question: How often do you release FREE updates of the TTM data? For how many
years do you plan on offering FREE TTM data updates for people who once
spent 20EUR on it? Maybe offering TTM data is becoming too cost-ineffective (licensing fees) for the MF company and will be discontinued due to lack of popularity within the MFN user community?