I don't believe any one of us is immune to a season of complaining once in a while, no matter how positive we attempt to live our lives the desire to complain is there. We might not understand something, see sense in a decision which was made, or even support it, and this emerges in a moment or season of complaint. Why? It is usually because we are disappointed, or maybe it is because we think we "knew better" or could have "done better". Sometimes rational thought does not enter into complaint, as with Job when he stood questioning his family's fate or the loss of all he had amassed. He didn't understand it, and this made his desire to complain surface a little. I don't think God wants us to live with a complaining type of mentality, never content or willing to accept what we receive, but I don't think he turns a deaf ear to our complaints either.
While we may not want to make a pattern or lifestyle out of complaining or finding fault in everything which doesn't seem to go as we planned or wanted, we don't have to fear God hearing our frustrations. He isn't put off by them - but he doesn't want us to dwell in that place too long. He wants us to get it out and move on - with his help, under his guidance, and with his strength. When we dwell there too long, we have a tendency to allow the complaint ushered because of some disappointment to escalate into a much deeper-seated sense of being "wronged" or "mistreated" or perhaps not "respected". We get a little bitter over the issue at hand and it begins to taint us toward resentment and anger over the situation.
If this occurs, we distance ourselves from truth just enough to continue to "nurse" our wounds over whatever frustration or disappointment first brought about this complaint in the first place. We magnify the issue until it takes center-stage in our lives and we begin to dwell on nothing other than whatever it is we see "wrong" in the matter. As God so aptly pointed out to Job, we don't always see things as they are, nor do we have the power within ourselves to change them even when we do. All that exists does so under God's watchful eye. All that occurs does so under his supervision. He isn't about to let one of his children fall into a trap, or walk away scathed by the issue.
Some may ask if God "creates" evil - since evil seems to be at the root of some of the things we become upset with and enter our complaints over. Evil exists because of sin - but God's children don't have to participate in evil's actions. We do get affected by their "drama" though. We see the actions of evil evident all around us - simply because man is sinful and apart from God's grace, their actions will lean toward being rooted in evil on occasion. When this occurs, we can become quite "put off" by their actions - simply because we don't understand them, nor do we support them. God's desire is for us to rise above evil, allowing him to protect us, but when his protection doesn't seem to take the course we expected, do we complain? Sometimes we do! We expected to never be affected by the evil and if we feel the effects, we kind of get our noses out of joint.
Instead of cursing evil, or standing in constant complaint over the manifest actions of evil, we would do well to bring our complaints to God - letting him know we don't understand it all, but trusting him to bring us through it in his grace. This may be all we can do, since we neither made the evil, nor do we understand it. Just sayin!