Short answer. Yes. A frustrated felony is punished one degree lower than the same crime completed. Article 50 sets that reduction for the principal, so stopping short of the intended result matters to the sentence — though whether the facts amount to a frustrated crime at all is decided on evidence.
What the law says
The penalty next lower in degree than that prescribed by law for the consummated felony shall be imposed upon the principal in a frustrated felony.
Revised Penal Code, Article 50 — Penalty For Frustrated Felony. Read the full provision →
The reduction is a step down a scale, not a discount
Article 50 says that the penalty next lower in degree than that prescribed by law for the consummated felony shall be imposed upon the principal in a frustrated felony. A degree is a position on the Code's ladder of penalties, so going one degree lower means moving to the penalty immediately below the one the law fixes for the finished crime. It is not a percentage taken off a number. That also means the first thing anyone has to establish is what the completed offence would carry, because the reduction is measured from that and from nothing else.
Frustrated does not mean nothing happened
The Code reserves the word for a narrow situation: the offender has already performed every act that would ordinarily produce the felony, and the felony still does not come about, for reasons independent of his will. A wound that would have been fatal but for surgery is the standard picture. If some act of execution was still missing, the case is not frustrated but attempted, which carries a different reduction. So the stage is not a matter of how the incident felt to anyone present; it turns on what acts were actually completed and why the result failed.
Money figures in the Code have been rewritten
One caution before anyone works out an expected sentence from a printed copy of the Revised Penal Code. Later legislation revised the fines and the property-value brackets running through the Code, and those amendments changed which penalty attaches to many offences measured by value. Article 50 itself was untouched, because it deals in degrees rather than in pesos, but the figure it reduces from may no longer be what an older text shows. Any calculation has to start from the amending statute, not from the original wording.
What the article settles and what it leaves open
This provision fixes the starting penalty for a principal in a frustrated felony. It does not fix the term the court will actually impose. That still depends on the rules for graduating penalties, on mitigating and aggravating circumstances, and on the sentencing law the court applies. Nor does the article decide the stage: whether the crime was frustrated, attempted or consummated is proved like any other fact. If you are involved in such a case, the documents that matter early are the information, the medical or forensic findings, and any account of what the accused did and stopped doing.