Despite 113 strategies on health and social care the system “feels close to collapse”, while economic productivity growth is “anaemic” despite 60 plans about the economy, the report said.
The Scottish Government has also struggled to hit its own targets on Net Zero carbon emissions by 2045 despite producing 82 plans and strategies on the issue since 2014.
The study said the failure by the Scottish Government to implement its own promises had “become a stain on devolution”.
The report, produced by the Our Scottish Future (OSF) think tank set up by former Labour PM Gordon Brown, looked at the shortfall between SNP policy promises and delivery.
It diagnosed some of the problems behind “Scotland’s implementation gap” and suggested a series of solutions inside the government, at Holyrood and across the UK.
However it said the most important thing would be a change of political culture, acknowledging that it could take another generation.
The report said the UK Government was also guilty of policy failures, citing the budget over-run and then part cancellation of the HS2 rail line as a classic example.
It also said the Scottish Government had a number of achievements to its credit, including the Queensferry Crossing, the Scottish Patient Safety programme and the National Manufacturing Institute for Scotland.
But on the other side of the balance sheet were problems with the Curriculum for Excellence, the delayed CalMac ferries and the unfilled Promise for care-experienced young people.
It said the “four big sources of failure” were “too much politics”, with multiple elections and referendums over the last decade, overlaid by arguments over the constitution.
This “perma-campaign” about independence meant every decision and announcement was viewed through an electoral and constitutional lens, with a lack of focus on delivery.
It also meant pro-Union opposition parties had “too often failed to set out an alternative policy agenda”, and this has “contributed to the lack of focus on implementation”.
There was also “too much government”, with too many ministers wanting to announce things, leading to recycled consultations and strategies and “government by press release”.
It said: “We see this in the ferry fiasco, in the failure to tackle the root causes of health inequalities, and in the gap between rhetoric and action on Net Zero.”
“There is a tendency to announce strategies and consultations rather than solid plans for action – on average, there has been more than one strategy and more than one consultation announced every single week for the past decade. This is announcing, not governing.”
Report author Jamie Gollings said the SNP’s desire for highlighting differences with Westminster meant there was also a failure to collaborate on UK-wide policies.
It meant “things best done in consort end up being done apart, less effectively and less efficiently”.
It criticised the “failure of Scotland’s political establishment to tackle these issues”, saying: “We have, collectively, lacked the focus and the courage to follow through on the policy choices we say we want to make.”
The was also a centralising culture in the Scottish Government, and an aversion to risk in case it upset voters about independence, leading to a lack of long-term planning.
The report suggested capping the number of ministers in the Scottish Government, more powerful scrutiny at Holyrood through paid and elected committee conveners, a “First Minister delivery unit” and a “beefed up Scottish Treasury” to improve the budget process.
“The measures we suggest would go some way to closing the implementation gap,” it said.
OSF chairman Professor Jim Gallagher said: “Government isn’t just about making speeches and publishing strategies, but implementing policies and delivering change.
“Scotland’s political culture has become one in which speeches are made, glossy documents are published, but too many things simply don’t get done.
“The first step to changing this problem is admitting that we have one.”
The Scottish Government has been asked for comment.