Got fired from a contract after 10 weeks despite turning the project around and getting an extension. How do I avoid this situation again?

Just got fired from a contract after ~10 weeks.

I was basically covering Product Owner, Project Manager, Support Lead, Business Analyst, Scrum Master, and at some points even QA roles.

Team was 6 people: 1 tech lead, 1 senior/lead dev, 2 mid devs, 1 QA, and me as PM/PO.

Project itself wasn't huge. It was a food bank platform consisting of 3 systems: storefront, point of sale, and admin console.

Timeline was roughly:

Week 1-2: Tech lead + senior dev join
Week 3: I join together with 2 mid devs
Week 5: QA joins
Week 6: We finally set a strategy how to move forward
Week 7-12: We deliver, but with lots of overtime, lots of unnecessary stress, having to constantly argue with techlead+senior dev about project direction and etc.

From week 1 until around week 6, the tech lead and senior dev were basically driving the project. The problem was that very little meaningful work was being delivered to the client, while the client was burning a lot of money on us.

So I took more initiative. Over the next ~6 weeks I got the timeline under control, pushed through some important wins, got us where we needed to be, and ultimately helped secure an extension of the contract. I even managed to get into a good working relationship with the "god complex" senior dev, who doesn't actually have too much of social skills...

Then on week 11 I got the news. The feedback was basically: I managed the project and client very well, but the team - mainly the tech lead, lead dev, and QA - wasn't happy with my soft skills. It was 2 days until my wedding, I was in a high stress situation already, COO was aware of all this, but still decided to dump this generic feedback on me. So I kinda went ballistic, reminding him how much effort I've put into managing the senior dev who is very rude, yet effective and so on.

And to be fair, there definitely was friction. I was constantly pushing back on the tech lead and lead dev about project strategy. They had also worked together before and came into this project as a package, while I was the outsider, most of the time it was 2v1 and I could barely win any arguments. Imagine that me as a PO/PM had to convince devs on the direction product is going, does that make any sense?

QA - was all over the place and I had to remind him multiple times what the priorities were. Eventually I called him out in the group chat in front of everyone. After that he started doing what was needed, but looking back, I can obviously see why that didn't exactly help the relationship.

What bothers me is that I feel like I was put into a situation where I had responsibility without clear authority.

Nobody communicated that the tech lead and senior dev expected to drive the project themselves. I'm 32 and these guys are roughly 36-45, with the tech lead being Director of Engineering level, so I expected that at minimum we'd establish who owns what and how decisions are made.

Instead, it felt like three people were trying to drive the same car at the same time.

They had the wheel for the first ~6 weeks, the project wasn't going anywhere, then I stepped in because somebody had to. We got the project back on track, hit the important deadlines, and got the extension.

Then I got bombarded with negative feedback and removed.

Based on the information I have, the lead dev basically gave an ultimatum behind the scenes: either he goes or I go. And from the company's perspective the choice isn't exactly difficult. If the PM has already gotten the project back on track and secured the extension, while the lead dev writes 90% of the code, you keep the lead dev.

So yeah. Lots of drama.

I feel like I participated in some kind of social experiment where the company wanted to see what happens when three people who all think they should drive the project are put together without clearly defining who actually has the wheel.

The soul-crushing part is that I pulled the project out of the ditch, got it across the finish line, and now I'm the one looking for another job.

I do have some takeaways from this.

I should've started 1:1s much earlier. I should've clarified the decision-making hierarchy, roles, and responsibilities on day one instead of assuming senior people would naturally sort that out.

And I definitely need to work on giving and receiving feedback. I can get too hot-headed, especially when I feel like criticism isn't based on the actual situation. Even when I think I'm right, how I communicate it obviously matters.

But I'm curious what experienced PMs/POs would take away from this.

How do you protect yourself from getting into projects like this?

What questions do you ask before joining a project to understand who actually has decision-making authority?

And most importantly, how do you make sure that if you're going to carry full responsibility for delivery, you're also given enough authority to actually do the job?