"My brethren, count it all joy when ye fall into divers temptation; knowing this, that the trying of your faith worketh patience.
But let patience have her perfect work, that ye may be perfect and entire wanting nothing."
James 1:2-4
Verse four doesn't say to let tests and trials have their perfect work; it says let patience have her perfect work.
Tests and trials don't perfect us. It is what we do with them that counts.
We aren't perfect because we have a bunch of problems but because we stick with God's Word in the midst of the problems.
That's when patience has its perfect work.
Patience is consistent endurance.
When we walk in patience, we remain consistent all the way through the situation, no matter what comes along.
We base everything on God's Word.
We get up in the morning and open the Bible and tell ourselves how we are according to the Word.
We can grow in our spiritual walk by using our faith against tests and trials.
Otherwise, we can go under. It's what we do with our problems that make us victorious or defeated.