Why do we face trials? The Bible has numerous ways of answering that question. Sometimes it's because God is exercising fatherly discipline (Hebrews 12). Sometimes it's due to consequences for sin (John 5:1-15). Sometimes it's because God wants to display His works through the hardship we're facing (John 9). Regardless, all trials test the authenticity of our faith.
But for whom?
God already knows whether or not your faith is real. It's not as if He isn't sure and has to send some hardship your way so He can find out. God doesn't sanction the trials we face so He'll know if our faith is legit. He sanctions the trials we face so we'll know if our faith is legit.
Suffering is a crucible. Through it, God says, "Now we're going to find out whether you got into this relationship with Me to serve Me or to get Me to serve you." The way we respond to trials either authenticates real faith or exposes our "faith" as fraudulent.
The 1 Peter passage ends this way...
"These [trials] have come so that the proven genuineness of your faith — of greater worth than gold...may result in praise, glory and honor when Jesus Christ is revealed."
May it be so!