Facilitation is so difficult but important skill

Today I had a meeting and discussion about problems. I joined it as a presenter and facilitator. That meeting had planned to finish in 1hour, but it took 2.5hour. The main reason was the miss of my facilitation maybe.

The topic of meeting was not light, so we needed to think carefully. Because I understood that, after explaining the solution plan, I said "let's discuss this plan. As a first step, we think about it 3 min. After that we give ideas." 
3 min later, we kept silent... but I thought I shouldn't make them hurry, so I didn't say anything. More 5 min one of them started talking but he didn't meet the point. I want to stop and change his opinion, but other one also started talking about different point. You know it was the situation of divergence. If I had high skill of facilitation, I got back the control and restarted that meeting, but I couldn't.

Finally we wasted 1.5hour to talk worthless talk. We got so tired. I deeply understood facilitation skill is difficult but important skill to rise the value of meeting. I try to raise the skill.